Benthic Habitats. 1.1 Introduction

Transcription

1 Benthic Habitats 1.1 Introduction This report aims at fulfilling the requirements of the EU Marine Strategy Framework Directive in describing the biological communities associated with predominant seabed habitats and assessing their status based on data existing to date. For the purposes of this report, data generated by marine surveys, including surveys commissioned in relation to the implementation of EU policies, and data originating from environmental assessment procedures was extracted and collated from the data repository of the Malta Environment and Planning Authority (MEPA). Efforts were made to supplement this data by scientific data from the published literature in an attempt to provide a complete overview of current knowledge on benthic habitats to the extent possible. Overall, the majority of the existing data pertains to inshore waters, with only sporadic data available for deeper offshore habitats. The uneven data distribution on marine habitats is attributed to the fact that ecological surveys in Malta throughout the past years focused on depths which could be reached by SCUBA diving and/or inshore areas subject to coastal developments. Deeper waters have only recently started being scientifically investigated 1. This data scenario precludes the possibility to assess all MSFD predominant benthic habitats at the same level of detail. Furthermore, current data limitations and gaps present significant difficulties in applying the MSFD criteria and indicators 2 for assessment of status. The predominant habitat types to be described and assessed for the purposes of the MSFD are established by the Commission Staff Working Paper 3. Depth zones with which the predominant habitat types are associated are specified in Table 1. Determination of these depth zones was based on the scientific literature, namely the RAC/SPA habitat classification 4 and Howell (2010) 5. The lower bathyal and the abyssal zones will not be considered any further in this report in view of data limitations Borg, J.A; Howege, H.M.; Lanfranco, E; Micallef, S.; Mifsud, C. & Schembri, P.J The Macrobenthic species of the infralittoral to circalittoral transition zone off the North-eastern coast of Malta (Central Mediterranean). Xjenza 3 (1); Commission Decision of 1 September 2010 on criteria and methodological standards on good environmental status of marine waters (2010/477/EU) Commission Staff Working Paper: Relationship between the initial assessment of marine waters and the criteria for good environmental status. SEC(2011)1255 final Established through the Protocol for Specially Protected Areas and Biodiversity in the Mediterranean (SPABIM), primarily based on the Peres & Picard scheme (1967) defining seven vertical marine zones Howell (2010) in 1

2 Table 1: Comparison of the marine zones associated with the MSFD Habitat Classification, the Peres & Picard scheme (1967) and their respective depth. MSFD habitat Peres & Picard Depth Topography classification scheme (1967) Littoral Mediolittoral 0m Coastal Waters Shallow sublittoral Infralittoral 0m 50m 6 Shelf sublittoral Circalittoral 50m 200m Continental Shelf 7 Upper Bathyal Bathyal 200m and 1100m 8 Continental slope Lower Bathyal 1,100m 2,700m 9 Abyssal Abyssal below 3000 m Abyssal plain Table 2 provides an indication of the benthic habitats which would fit into each of the MSFD predominant habitat type category as stipulated by the Commission Staff Working Paper. The content of this table is based on an exercise carried out by Borg & Schembri (2002) 10, through which local marine habitats data was aligned with habitat types as listed in the EU Habitats Directive (92/43/EEC) and the RAC/SPA habitat classification 11. This exercise focused on the inshore or coastal areas thus covering the littoral, shallow sublittoral and partly the shelf sublittoral MSFD habitat types. Marine habitat types representing the shelf and bathyal habitat types were extrapolated from the EUNIS classification of habitats. This report, which was compiled by MEPA in consultation with Professor P.J. Schembri and Dr. J.A. Borg, experts in the field of marine biology, provides a brief description of the benthic habitats within each MSFD predominant habitat type category, an indication of the pressures exerted on such habitats by anthropogenic activities and an assessment of status, where possible. Although the present report provides a general description of the habitat types at a National scale, assessment areas, which would vary for different habitat types, were defined for the purposes of assessment of status. The information provided in this report is based on existing data, hence the different levels of detail provided for the different habitat types The boundary between the shallow sublittoral and shelf sublittoral MSFD habitat types was set at 50m, based on the vertical extent of occurrence of marine phanerograms, namely Posidonia oceanica in Malta. In the Maltese Islands, the maximum depth at which stands of this species have been recorded is 44m (Borg J. A., Micallef M. A, & Schembri P. J., Spatio-temporal variation in the structure of a deep water Posidonia oceanica meadow assessed using non-destructive techniques. Marine Ecology 27: ) Definition of continental shelf by the Continental Shelf Act: "the continental shelf" means the sea bed and subsoil of the submarine areas adjacent to the coast of Malta but outside territorial waters, to a depth of two hundred metres or, beyond that limit, to where the depth of the superjacent waters admits of the exploitation of the natural resources of the said areas Howell (2010) in ditto Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 Established through the Protocol for Specially Protected Areas and Biodiversity in the Mediterranean (SPABIM) 2

3 Table 2: Habitat types considered for the purposes of the MSFD based on Borg & Schembri (2002) and the EUNIS classification of habitats. Subcomponents based on the RAC- MSFD classification of habitats 12 EUNIS code SPA habitat types 13 and Borg & Relevant EUNIS codes for sub-components Schembri (2002) 14 Littoral rock and biogenic reef Littoral sediment A1: Littoral Rock and other hard substrata A2: Littoral Sediment Biocoenosis of the upper mediolittoral rock (II.4.1) Biocoenosis of the lower mediolittoral rock (II.4.2) Mediolittoral caves (II.4.3) A1.13: Mediterranean and Black Sea Communities of upper mediolittoral rock A1.14: Mediterranean and Black Sea Communities of Lower Mediolittoral rock very exposed to wave action A1.23: Mediterranean Communities of lower mediolittoral rock moderately exposed to wave action A1.34: Mediterranean Communities of lower mediolittoral rock sheltered from wave action A1.44: Communities of littoral caves and overhangs Biocoenosis of muddy sands and muds (II.1.1) A2.5: Coastal saltmarshes and saline reedbeds A2.2: Littoral Sand and muddy sand Biocoenosis of mediolittoral sands (II.2.1) A2.25: Mediterranean and Pontic Communities of mediolittoral sands A2.1: Littoral coarse sediments Biocoenosis of mediolittoral coarse detritic A2.13: Mediterranean communities of mediolittoral coarse bottoms (II.3.1) detritic bottoms Shallow sublittoral rock and biogenic reef A3: Infralittoral rock and other hard substrata Biocoenosis of infralittoral algae (III.6.1) A3.1: A3.13: Mediterranean and Pontic communities of infralittoral algae very exposed to wave action A3.14: Encrusting algal communities A3.15: Frondose algal communities (other than kelp) A3.23: Mediterranean and Pontic communities of infralittoral algae MSFD Habitat Classification as defined by the Commission Staff Working Paper: Relationship between the initial assessment of marine waters and the criteria for good environmental status [SEC(2011)1255 final] Established through the Protocol for Specially Protected Areas and Biodiversity in the Mediterranean (SPABIM) Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs

4 MSFD classification of habitats 12 EUNIS code Subcomponents based on the RAC- SPA habitat types 13 and Borg & Schembri (2002) 14 Relevant EUNIS codes for sub-components moderately exposed to wave action; A3.33: Mediterranean submerged fucoids, green or red seaweeds on full salinity infralittoral rock; Shallow sublittoral coarse sediment Shallow sublittoral sand Shallow sublittoral mud A5.5: Macrophyte dominated sediment (?) A5: Sublittoral sediment [A5.1 sublittoral coarse sediments] A5: Sublittoral sediment A5: Sublittoral sediment Posidonia oceanica meadows (III.5) Biocoenosis of infralittoral coarse sands and fine gravels mixed by waves (III.3.1) Biocoenosis of infralittoral stones and pebbles (III.4.1) Biocoenosis of infralittoral gravels Biocoenosis of fine sands in very shallow waters (III.2.1) Biocoenosis of well sorted fine sands (III.2.2) Biocoenosis of superficial muddy sands in sheltered waters (III.2.3) Posidonia oceanica meadows (III.5) Biocoenosis of polluted harbour mud and sandy mud A4.26: Mediterranean coralligenous communities moderately exposed to hydrodynamic action A5.5: Sublittoral macrophyte-dominated sediment A5.53: Sublittoral seagrass beds A5.1: Sublittoral coarse sediments A5.13: Infralittoral coarse sediment A5.1: Sublittoral coarse sediments A5.13: Infralittoral coarse sediment A5.1: Sublittoral coarse sediments A5.13: Infralittoral coarse sediment A5.2: Sublittoral Sand A5.23: Infralittoral fine sand A5.5: Sublittoral macrophyte-dominated sediment A5.53: Sublittoral seagrass beds A5.2: Sublittoral Sand A5.28: Mediterranean communities of superficial muddy sands in sheltered waters A5.5: Sublittoral macrophyte-dominated sediment A5.53: Sublittoral seagrass beds A5.5: Sublittoral macrophyte-dominated sediment A5.53: Sublittoral seagrass beds A5.3: Sublittoral mud A5.5: Sublittoral macrophyte-dominated sediment 4

5 MSFD classification of habitats 12 Shallow sublittoral mixed sediment Shelf sublittoral rock and biogenic reef Shelf sublittoral coarse sediment Shelf sublittoral sand EUNIS code [& A5.5: Sublittoral macrophyte-dominated sediment] A5: Sublittoral sediment A4: Circalittoral rock and other hard substrata A5: Sublittoral sediment A5: Sublittoral sediment Subcomponents based on the RAC- SPA habitat types 13 and Borg & Schembri (2002) 14 Sandy muds, sands, gravels and rocks in euryhaline and eurythermal environment (III.1) Biocoenosis of infralittoral coarse sands and muddy heterogenous sediments Circalittoral Coralligenous biocoenosis (IV.3.1) Circalittoral Semi-dark caves (IV.3.2) Biocoenosis of shelf-edge rock (IV.3.3) Biocoenosis of coarse sands and fine gravels under the influence of bottom currents (maerl facies and association with rhodoliths) (III.3.2) Biocoenosis of circalittoral coarse sands and fine gravels under the influence of bottom currents (IV.2.4). Circalittoral Sands (IV.2) Relevant EUNIS codes for sub-components A5.53: Sublittoral seagrass beds A5.5: Sublittoral macrophyte-dominated sediment A5.52: Kelp and seaweed communities on sublittoral sediment. A5 including A5.53 Sublittoral seagrass beds A4.2: Atlantic and Mediterranean circalittoral rock A4.26: Mediterranean coralligenous communities moderately exposed to hydrodynamic action; A4.3: Atlantic and Mediterranean low energy circalittoral rock A4.32: Mediterranean coralligenous communities sheltered from hydrodynamic action A4.33: Faunal communities on deep low energy circalittoral rock; A4.7: Features of circalittoral rock A4.71: Communities of circalittoral caves and overhangs A4.2 Atlantic and Mediterranean circalittoral rock A5.5: Sublittoral macrophyte-dominated sediment A5.51: Maerl beds A5.14: Circalittoral coarse sediment A5.2: Sublittoral sand A5.25: Circalittoral fine sand A5.26: Circalittoral muddy sediments 5

6 MSFD classification of habitats 12 Shelf sublittoral mud Shelf sublittoral mixed sediment Upper bathyal rock and biogenic reef EUNIS code A5: Sublittoral sediment A5: Sublittoral sediment A6: Deep seabed Upper bathyal sediment A6: Deep seabed Subcomponents based on the RAC- SPA habitat types 13 and Borg & Schembri (2002) 14 Biocoenosis of coastal terrigenous muds (IV.1.1) Biocoenosis of the muddy detritic bottom (IV.2.1) Biocoenosis of the circalittoral coastal detritic bottom (IV.2.2) Biocoenosis of shelf-edge detritic bottom (IV.2.3) Biocoenosis of deep sea corals (V.3.1) Caves and ducts in total darkness (V.3.2) Deep-sea bioherms Biocoenosis of bathyal muds (V.1.1) Biocoenosis of bathyal detritic sands with Grypheus vitreus (V.2.1) Biocoenosis of bathyal detritic sands with Grypheus vitreus (V.2.1) Relevant EUNIS codes for sub-components A5.3: Sublittoral Mud A5.39: Mediterranean commuities of coastal terrigenous muds A5.3: Sublittoral Mud A5.38: Mediterranean communities of muddy detritic bottoms A5.39: Mediterranean commuities of coastal terrigenous muds A5.4: Sublittoral mixed sediment A5.46: Mediterranean animal communities of coastal detritic bottoms A5.51: Maerl beds A5.52: Kelp and seaweed communities on sublittoral sediment A5.47: Mediterranean communities of shelf-edge detritic bottoms A6.61: Communities of deep-sea corals A4.71: Communities of circalittoral caves and overhangs A6.62: Deep-sea sponge aggregations A6.51: Mediterranean communities of bathyal muds A6.31: Communities of bathyal detritic sands with Grypheus vitreus A6.31: Communities of bathyal detritic sands with Grypheus vitreus 6

7 1.2 Relevant Legislation and Management Activities The marine environment is governed by various policies at local, regional and international level calling for the conservation of marine habitats and species or the management of marine activities which may impact on marine habitats and species. Most of these policies are to some extent or other linked to the implementation of the Marine Strategy Framework Directive. This section briefly outlines the main legislative tools which are relevant to the conservation of marine benthic habitats. Table 3 lists the policies which are deemed relevant for the purposes of MSFD implementation. Table 4 outlines the relations between the benthic habitats listed under the various policies and the MSFD predominant habitat types as identified by the Commission Staff Working Paper EU legislation EU Nature Directives and the EU Biodiversity Strategy to 2020 The EU Nature Directives comprise the Habitats Directive (92/43/EEC) and the Birds Directive (2009/147/EC), which are locally transposed to national law through the Flora, Fauna and Natural Habitats Protection Regulations, 2006 (Legal Notice 311 of 2006 as amended) and the Conservation of Wild Birds Regulations, 2006 (Legal Notice 79 of 2006 as amended). These regulations provide for the designation of protected areas in the marine environment. Designated protected areas falling within the criteria of the Nature Directives form part of the EU Natura 2000 network of protected areas, which is aimed at maintaining or restoring natural habitats and species listed in the Directive at a Favourable Conservation Status. The Directives also call for the strict protection of species, particularly all native wild birds (including seabirds) and species listed in Annex IV of the EU Habitats Directive. The goals of the EU Habitats Directive in restoring or maintaining listed marine habitats and species at a Favourable Conservation Status are in line with those of the Marine Strategy Framework Directive in achieving Good Environmental Status in marine waters. The EU MSFD widens this scope to cover habitat types other than those listed in the annexes to the Habitats Directive. The EU Biodiversity Strategy 2020 calls for the fulfilment of the Habitats Directive with a view to halt the deterioration in the status of all species and habitats covered by EU nature legislation and achieve a significant and measurable improvement in their status so that by 2020, 100% more habitat assessments occur and 50% more species assessments under the Habitats Directive show an improved conservation status. 7

8 Water Framework Directive (2000/60/EC) The EU Water Framework Directive (WFD) 2000/60/EC focuses on the protection of all water resources, including coastal waters. For the purposes of the WFD, the coastal waters around the Maltese Islands have been divided into 9 distinct water bodies, the boundaries of which were determined on the basis of the predominant physical and ecological characteristics, as well as on the nature and magnitude of pressures on the coastal water environment. Two of the nine water bodies designated around the Maltese Islands, namely the harbour areas (Il-Port il-kbir and Il-Port ta Marsamxett; Il-Port ta Marsaxlokk) are Heavily Modified Water Bodies 15. The main objective of the WFD for coastal water bodies is the achievement, by 2015, of good ecological status up to one nautical mile from the coast; good chemical status for all territorial waters (12 nautical miles) and good ecological potential 16 for heavily modified water bodies. Good ecological status is defined by the ecological status of biological elements, including elements associated with benthic habitats such as seagrasses, macroalgae and benthic invertebrates. Achievement of such good status would contribute to the achievement of Good Environmental Status for benthic habitats within the framework of the MSFD. Malta s Water Catchment Management Plan 17 identifies a series of measures aimed at achieving the goals of the WFD for the identified water bodies. Through this plan, Malta is also requesting exemptions to achieving good status for three coastal water bodies Regional Conventions and/or International Agreements Convention on Biological Diversity The Convention on Biological Diversity (CBD) is a major UNEP-driven multilateral environment agreement targeted at the conservation of biological diversity, the sustainable use of its components, and the fair and equitable sharing of the benefits arising from the utilisation of genetic resources. The CBD also calls for the identification of ecologically or biologically significant areas (EBSAs) in marine areas beyond national Heavily Modified Water Bodies are substantially changed in character as a result of physical alterations by human activity, and cannot therefore, meet good ecological status Good Ecological Potential is less stringent objective than good ecological status, making allowances for ecological impacts resulting from alterations to the physical environment that are necessary to either support a specific use, or must be maintained in order to avoid effects on the wider environment

9 jurisdiction, based on scientific criteria as contained in Annex I to CBD Decision IX/20. In October 2010, the Conference of Parties of the CBD adopted a revised and updated strategic plan for biodiversity, which includes the Aichi Biodiversity Targets aimed at achieving the objectives of the Convention. These targets have been taken on board by the Malta s National Biodiversity Strategy and Action Plan 19. The Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention) The Council of Europe s Bern Convention aims at the conservation of European wild flora and fauna and their natural habitats, with a particular focus on the protection of endangered natural habitats and endangered species. The natural habitat types requiring specific conservation measures are listed in Resolution No. 4 (1996) adopted by the Standing Committee of the Convention on 6 December In 2010, this list was revised in line with the EUNIS Habitat Classification. The provisions of the Bern Convention are addressed through the Flora, Fauna and Natural Habitats Protection Regulations, 2006 (Legal Notice 311 of 2006 as amended), which is the National legal instrument transposing the requirements of the EU Habitats Directive and various biodiversity-related multilateral environment agreements. The Convention for the Protection of the Mediterranean Sea against Pollution (Barcelona Convention) The Barcelona Convention led to a protocol concerning Mediterranean Specially Protected Areas in 1982, which was amended and renamed the Protocol for Specially Protected Areas and Biodiversity in the Mediterranean (SPABIM) in Parties to this protocol are obliged to establish protected areas and to undertake all actions necessary in order to protect these areas and, as appropriate, to restore them as rapidly as possible. The protocol lists habitat types for the selection of sites to be included in National inventories of Natural Sites of Conservation Interest, which list was finalised by the 4th meeting of the National Focal Points for SAP and cleared by the meeting of MAP focal points on the 6 September 1999 in Athens. The provisions of this protocol are addressed through the Flora, Fauna and Natural Habitats Protection Regulations, 2006 (Legal Notice 311 of 2006 as amended), which is the National legal instrument transposing the

10 requirements of the EU Habitats Directive and various biodiversity-related multilateral environment agreements.. Table 3: List of regional and EU policies relevant to MSFD implementation with respect to benthic habitats Policies relevant to marine benthic habitats Convention on Biological Diversity Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention) Protocol for Specially Protected Areas and Biological Diversity in the Mediterranean of the Barcelona Convention Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora (Habitats Directive) The Convention on Wetlands (Ramsar Convention) Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy (Water Framework Directive) Council Regulation 1967 of 2006 concerning management measures for the sustainable exploitation of fishery resources in the Mediterranean Sea Equivalent legislation at National scale Convention on Biological Diversity Incorporation Regulations, 2002 (Legal Notice 160 of 2002) Flora, Fauna and Natural Habitats Protection Regulations, 2006 (Legal Notice 311 of 2006 as amended) Conservation of Wild Birds Regulations, 2006 (Legal Notice 79 of 2006 as amended) Malta s National Biodiversity Strategy and Action Plan Water Policy Framework Regulations, 2004 (Legal Notice 194 of 2004) Directly Applicable 10

11 Table 4: Listed marine habitat types as per EU Habitats Directive, Barcelona Convention and the Bern Convention within each MSFD habitat category. MSFD Habitat Classification Littoral rock and biogenic reef Littoral sediment Shallow sublittoral rock and biogenic reef Annex I habitat types Habitats Directive Habitat types for the selection of sites to be included in the National Inventories of Natural Sites of Conservation Interest as finalised by the 4 th meeting of the National Focal Points for SPA (Tunis, April 1999) Habitat types listed as endangered natural habitat types requiring specific conservation measures under the Bern Convention (Emerald Network) in accordance with Resolution No. 4 (1996) make a note of the mixture of using EUNIS and Emerald Network codes Reefs (1170) Association with Lithophyllum lichenoides (II.4.2.1) Association with [Lithophyllum byssoides] (A1.141) Neogoniolithon brassica-florida concretion Moderate energy littoral rock (A1.2) (II.4.2.8) Pools and lagoons sometimes associated with vermetids (II ) Submerged or partially submerged sea Association with Phymatolithon lenormandii and Communities of littoral caves and caves (8330) Hildenbrandia rubra (II.4.3.1) overhangs (A1.44) Coastal lagoons (1150) Association with halophytes (II.1.1.1) Coastal saltmarshes and saline reedbeds (A2.5) Facies of banks of dead leaves of Posidonia oceanica and other phanerograms Littoral Sand and muddy sand (A2.2) Reefs (1170) Association with Cystoseira amentacea (III.6.1.2) Submerged or partially submerged sea Facies with vermetids (III.6.1.3) caves (8330) Facies with Cladocora caespitosa (III ) Association with Cystoseira brachycarpa (III ) Association with Cystoseira crinita (III ) Association with Cystoseira crinitophylla (III ) 11

12 Association with Cystoseira spinosa (III ) Association with Sargassum vulgare (III ) Facies and associations of coralligenous biocoenosis (III ) Mediterranean coralligenous communities moderately exposed to hydrodynamic action (A4.26) Posidonia beds (1120) Seagrass meadows (11.3) Shallow sublittoral coarse sediment Sandbanks which are slightly covered by seawater all the time (1110) Seagrass meadows (11.3) Sublittoral soft seabeds (11.22) Shallow sublittoral sand Sandbanks which are slightly covered by seawater all the time (1110) Seagrass meadows (11.3) Association with Halophila stipulacea (III.2.2.2) Posidonia beds (1120) Ecomorphosis of barrier reef meadows Facies with Loripes lacteus and Tapes spp. Sublittoral soft seabeds (11.22) (III.2.3.3) Shallow sublittoral mud Sublittoral soft seabeds (11.22) Shallow sublittoral mixed sediment Shelf sublittoral rock and biogenic reef Reefs (1170) Submerged or partially submerged sea caves (8330) Association with Ruppia cirrhosa and/or Ruppia elongata (III.1.1.1) Association with Halopitys elongata (III.1.1.8) Association with Cystoseira zosteroides (IV.3.1.1) Association with Cystoseira usneoides (IV.3.1.2) Association with Cystoseira dubia (IV.3.1.3) Association with Cystoseira corniculata (IV.3.1.4) Association with Sargassum sp. (IV.3.1.5) Association with Laminaria ochroleuca (IV.3.1.8); Association with Rodriguezella strafforelli (IV.3.1.9); Facies with Eunicella cavolinii (IV ); Facies with Eunicella singularis (IV ); Facies with Lophogoria sarmentosa (IV ); Sublittoral soft seabeds (11.22) Mediterranean coralligenous communities moderately exposed to hydrodynamic action (A4.26); Mediterranean coralligenous communities sheltered from hydrodynamic action (A4.32) Mediterranean coralligenous communities moderately exposed to hydrodynamic action (A4.26) Mediterranean coralligenous 12

13 Shelf sublittoral coarse sediment communities sheltered from hydrodynamic action (A4.32) Facies with Paramuricea clavata (IV ); Mediterranean coralligenous Coralligenous platforms (IV ) communities moderately exposed to hydrodynamic action (A4.26) Facies with Corallium rubrum (IV.3.2.2) Communities of circalittoral caves and overhangs (A4.71) Association with rhodoliths (III.3.1.1) Sublittoral soft seabeds (11.22) Maerl facies (= Association with Lithothamnion corallioides and Phymatolithon calcareum) (III.3.2.1) Association with rhodoliths (III.3.2.2) Shelf sublittoral sand Sublittoral soft seabeds (11.22) Shelf sublittoral mud Sublittoral soft seabeds (11.22) Shelf sublittoral mixed sediment Association with Laminaria rodriguezii on detritic (IV.2.2.7) Sublittoral soft seabeds (11.22) Facies with large Bryozoa (IV ) Upper bathyal rock and Reefs (1170) Biocoenosis of deep sea corals (V.3.1) biogenic reef Caves and ducts in total darkness (V.3.2) Communities of circalittoral caves and overhangs (A4.71) Upper bathyal sediment Facies of soft muds with Funiculina quadrangularis and Apporhais seressianus (V.1.1.3) Reefs (1170) Facies of compact muds with Isidella elongata (V.1.1.4) 13

14 1.2.3 Other policies Council Regulation (EC) No 1967/2006 concerning management measures for the sustainable exploitation of fishery resources in the Mediterranean Sea, relates to the conservation, management and exploitation of living aquatic resources in the Mediterranean. This regulation constitutes a number of provisions related to the conservation of marine resources including the regulation or prohibition of specific fishing activities on protected or sensitive habitats, in particular Posidonia oceanica, coralligenous habitats, maerl beds and corals. The regulation also calls for the establishment of Fishing Protected Areas in which fishing activities may be banned or restricted in order to conserve and manage living aquatic resources or maintain or improve the conservation status of marine ecosystems; and for the adoption of management plans for specific Mediterranean fisheries. The regulation adopts the 25-mile Fisheries Management Zone around the Maltese Islands and stipulates provisions regulating fishing within this zone Protected areas Malta has designated five Special Areas of Conservation in the marine environment within the framework of the Habitats Directive (92/43/EEC), published as per Government Notice 851 of 2010 (Figure 1). The designation of these Marine Protected Areas was mainly based on the presence of Posidonia oceanica meadows as a priority habitat type of the Habitats Directive. 14

15 Figure 1: Marine Special Areas of Conservation in Malta 15

16 1.3 Benthic habitats Characteristics Littoral Rock and Biogenic Reef According to published information, rocky shores make up circa 90% of the Maltese coastline 20, with gently sloping shores prevailing along the North-eastern coastline of the islands and sheer vertical cliffs characterising the Southwestern coast. The gently sloping shores support macroalgal communities occupying the lower mediolittoral zone, generally characterised by belts of Cystoseira species in well-lit places and Corallina elongata in shaded places. Platforms formed by the alga Neogoniolithon brassica-florida and the vermetid Dendropoma petraeum are also reported to be common on such shores 21. The sheer vertical cliffs represent a favourable substratum for biogenic concretions such as those of Lithophyllum byssoides. They also support a number of mediolittoral caves formed by the direct action of the sea on the limestone rock at sea level. These caves are generally characterised by three distinct zones, the extent of which would depend on physiographic conditions 22 : an outer zone where some light penetrates allowing the growth of photophilic algae at the opening with progressively more sciaphilic species further inwards from the mouth; a middle section dominated by sessile invertebrates (sponges, corals, tubicolous polychaetes, bryozoans, hydroids, brachiopods and foraminifera) with few algae, almost all encrusting corallines; a completely dark inner section largely devoid of sessile organisms. The macroalgal communities along the mediolittoral zone were studied at a National scale through a 2008 survey 23 aimed at the application of the CARLIT 24 methodology for the determination of ecological status of the Maltese littoral rock. This methodology is being currently applied to evaluate the quality of coastal waters as part of the monitoring programme of the Water Framework Directive, the official Gauci, M.; Deidun, A. & Schembri, P.J Faunistic diversity of Maltese pocket sandy and shingle beaches: are these of conservation value? Oceanologia 47 (2) pp Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34: 128 Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 Thibaut, T Ecological Status of the Rocky Coast of Malta, May 2008 Cartography of littoral and upper-sublittoral benthic communities as an approach to use macroalgae as a key biological quality element for the assessment of the ecological status in coastal waters in the frame of the European Water Framework Directive Ballesteros, E.; Torras, X; Pinedo, S.; Garcia, M.; Mangialajo, L. & detorres, M A new methodology based on littoral community cartography dominated by macroalgae for the implementation of the European Water Framework Directive. Marine Pollution Bulletin 55:

17 results of which will be available by June The distribution of algal communities, Lithophyllum byssoides trottoirs and caves on the lower mediolittoral as mapped through the 2008 CARLIT survey is shown in Figure 2 and 25 CIBM & Ambiente SC Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys Water Lot 3 Surveys of Coastal Water August ERDF156 - Developing national environmental monitoring infrastructure and capacity 17

18 Figure 3. The CARLIT data on caves was supplemented by published information on this habitat type 26. Both the 2008 and 2012 surveys confirm that Cystoseira amentacea var. stricta is the most abundant species for this habitat type, accompanied by other Cystoseira species including C. crinita, C. compressa and C. brachycarpa. Cystoseira amentacea var. stricta occupies, albeit at varying densities, about 57% (>112km over 195km mapped coastline) of the total Maltese rocky shores. The distribution pattern of the algal communities dominated by C. amentacea var. stricta is shown in Figure 4. When Cystoseira beds are absent, gently sloping coastlines are characterised by assemblages dominated by other algal species including Laurencia sp., Dictyota sp and Dictyopteris polypodioides 27. In disturbed areas Cystoseira species are generally replaced by calcareous alga such as Corallina elongata and Enteromorpha (=Ulva) species, both of which, where they occur at high densities in the absence of Cystoseira species, can be considered to be indicators of reduced water quality, particularly due to the presence of nitrate and phosphate pollution 28. Such degraded zones are mainly located in ports and inner parts of bays subject to anthropogenic disturbance (J.A. Borg & P.J. Schembri, personal communication). A stretch of coastline along the North-eastern coast of Malta, which until recently was subject to discharge of untreated sewage, is also devoid of Cystoseira belts. The sewage outfall has been replaced by treated sewage effluent in 2012, however it is too early to detect any changes in algal communities as a result of such replacement Wood, L.. & Wood, L : The Dive Sites of Malta, Comino & Gozo. Comprehensive Coverage of Diving and Snorkelling: Progress Press, 111pp.; Aquilina, S. 1995: Treasures of the Maltese Waters. Part One. Shore Dives: Aquilina Enterprises Ltd, 63pp.; Lemon, P.G. (ND): Scuba Diving Malta, Gozo, Comino: MGP Books Group, 224pp.; Middleton, N. (1997): Maltese Islands Diving Guide: Miller Distributors Ltd, 167pp. CIBM & Ambiente SC Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys Water Lot 3 Surveys of Coastal Water August ERDF156 - Developing national environmental monitoring infrastructure and capacity Thibaut, T Ecological Status of the Rocky Coast of Malta, May

19 Figure 2: Distribution of habitats associated with Littoral Rock on the Maltese Islands (Source: Thibaut, 2011) Thibaut, T Ecological Status of the Rocky Coast of Malta, May

20 Figure 3: Indication of the location of mediolittoral caves based on the surveys carried out by Thibaut, and other published information Thibaut, T Ecological Status of the Rocky Coast of Malta, May 2008 Wood, L.. & Wood, L : The Dive Sites of Malta, Comino & Gozo. Comprehensive Coverage of Diving and Snorkelling: Progress Press, 111pp.; Aquilina, S. 1995: Treasures of the Maltese Waters. Part One. Shore Dives: Aquilina Enterprises Ltd, 63pp.; Lemon, P.G. (ND): Scuba Diving Malta, Gozo, Comino: MGP Books Group, 224pp.; Middleton, N. (1997): Maltese Islands Diving Guide: Miller Distributors Ltd, 167pp. 20

21 Figure 4: Distribution pattern in terms of density of Cystoseira amentacea var. stricta as reported by Thibaut (2011) 32 Pressures Degradation in water quality is considered to be the major threat to Cystoseira communities on lower mediolittoral rock. Thibaut (2011) 33 attributes changes in biological communities on littoral rock to reduced water quality, specifically to nutrient enrichment. Nutrient enrichment in Malta is mainly associated with sewage outfalls and overflows, port operations and agricultural runoff (J.A. Borg & P.J. Schembri, personal communication). Within this context, it should be noted that all municipal wastewater is now being treated and second class treated wastewater is currently being discharged from wastewater treatment plants. Cystoseira communities are also negatively affected by increase in turbidity of coastal waters as a result of anthropogenic activities such as dredging, boating and port operations, as well as a result of run-off. Coastal development resulting in replacement of rocky shoreline with artificial coastline, does not generally lead to physical loss of algal communities along the mediolittoral zone, since such algae can equally colonise natural rock and artificial substrata (J.A. Borg & P.J. Schembri, personal communication). Nevertheless, replacement of a gently sloping rocky shore with a vertical artificial coastline, would reduce the surface area available for colonisation and change light conditions, Thibaut, T Ecological Status of the Rocky Coast of Malta, May 2008 Thibaut, T Ecological Status of the Rocky Coast of Malta, May

22 potentially resulting in narrower algal belts along the shoreline and in changes in the composition of algal communities. A study carried out as part of the Interreg IIIC DEDUCE project 34 indicated that between the period 1994 and 2004 there was an increase of 1% in artificial coastline. Development along the coast of the Maltese Islands is mostly related to harbour, recreation or road development infrastructure, rather than to coastal defence structures. Other impacts on littoral rock communities may arise from discharges of brine water from desalination plants and of cooling waters from power plants. Such discharges may create localised changes in salinity regimes, potentially leading to changes in species composition of macroalgae on the lower mediolittoral. Nevertheless such impacts are highly localised and are deemed to be of low significance. The same applies to the potential disturbance along the coastline caused by the laying down of submarine cables and pipelines. Such disturbance is deemed to be both localised and temporary, since macroalgae are likely to recolonise the disturbed areas. SCUBA diving is the main source of pressures on the submerged portion of emergent sea caves and underwater caves. Diving may cause both mechanical damage to erect sessile forms growing in caves, and death of the biota on the ceiling due to trapped air bubbles from diving cylinders 35. In the protected Qawra/Dwejra area, frequent visits in caves by SCUBA divers are known to have resulted in destruction of fragile bryozoan colonies growing on the roof of the caves 36. Boating activities may also have an impact on the biota of the emerged portions of littoral caves (P.J. Schembri, personal communication) Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34: 128 Borg J. A., Micallef S. A., Pirotta K., Schembri P. J., Baseline marine benthic surveys in the Maltese Islands (Central Mediterranean). In E. Ozhan (ed.) Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST ë97, November 11-14, 1997, pp v figs. 22

23 1.3.2 Littoral Sediment The MSFD Littoral Sediment habitat type includes sandy and shingle beaches along the shoreline; boulder shores are considered as littoral rock. Sandy (particle size mm), shingle (particle size 2-256mm) or mixed sand and shingle shores are restricted to small pockets along the Maltese coast occupying circa 2.4% of the Maltese coastline or an estimate of 6.5km 37. In general, circa 6km of the coastline is sandy, while c. 0.6km is shingle 38. Figure 5 indicates the distribution of sandy and shingle beaches on the Maltese coastline. Most of the minor beaches included in this figure are highly susceptible to natural factors, such as storms, and their extent would vary seasonally, with some beaches completely disappearing from the littoral zone during the winter months (P.J. Schembri & J.A. Borg, personal communication). The ecology of sandy and shingle beaches is not well known in Malta, however they are generally characterised by an impoverished species richness and abundance 39. To date, the poor biodiversity associated with sandy or shingle beaches can neither be attributed to natural factors nor to anthropogenic disturbance. Nonetheless, in view of their restricted distribution, sandy or shingle beaches create habitats of high conservation value supporting rare species. Furthermore, each beach is considered to be ecologically isolated, especially to species with limited dispersal powers, hence each beach is associated with unique assemblages of species 40,41. To date, such differences in faunal species across beaches cannot be explained in terms of different abiotic factors and further studies are deemed necessary 42. A study carried out on eight sandy beaches on mainland Malta and two on Gozo resulted in the collection of only 16 species from mediolittoral and uppermost infralittoral zones 43. A comparative study on sandy and shingle beaches indicated that while species richness and abundance were generally low on both shore types, these parameters were higher on the wet zones of shingle beaches when compared to same zones on sandy beaches 44. Overall, species associated with sandy and Gauci, M.; Deidun, A. & Schembri, P.J Faunistic diversity of Maltese pocket sandy and shingle beaches: are these of conservation value? Oceanologia 47 (2) pp ditto Deidun, A. Azzopardi, M., Saliba, S. & Schembri, P.J Low faunal diversity on Maltese sandy beaches: fact or artefact? Estuarine, Coastal and Shelf Science 58S: Deidun, A. Azzopardi, M., Saliba, S. & Schembri, P.J Low faunal diversity on Maltese sandy beaches: fact or artefact? Estuarine, Coastal and Shelf Science 58S: Gauci, M.; Deidun, A. & Schembri, P.J Faunistic diversity of Maltese pocket sandy and shingle beaches: are these of conservation value? Oceanologia 47 (2) pp Deidun, A. Azzopardi, M., Saliba, S. & Schembri, P.J Low faunal diversity on Maltese sandy beaches: fact or artefact? Estuarine, Coastal and Shelf Science 58S: ditto Gauci, M.; Deidun, A. & Schembri, P.J Faunistic diversity of Maltese pocket sandy and shingle beaches: are these of conservation value? Oceanologia 47 (2) pp

24 shingle beaches are considered to be among the most endangered of the local biota 45. Species which are generally associated with the wet zones on sandy beaches, and are thus of relevance to the MSFD, include the polychaete Ophelia bicornis, the isopods Tylos europaeus occurring only on sandy beaches, Tylos ponticus occurring on gravel, pebble and cobble, and talitrid amphipods 46 (J.A. Borg & P.J. Schembri, personal communication). Until 2003, O. bicornis was solely recorded from the sandy beach at Ir-Ramla in Gozo and T. europaeus from White Tower Bay on mainland Malta 47. However research efforts on sandy or shingle beaches undertaken to date are not deemed adequate enough to provide a clear picture of the actual distribution of these species on Maltese beaches, also in view of the rarity of such species. In fact, experts can now confirm the presence of these species on other beaches (J.A. Borg & P.J. Schembri, personal communication). There are unpublished records of O. bicornis at Ir-Ramla tal-mixquqa and T. europaeus has also been recorded at San Blas in Gozo 48. However data on the abundance or biomass of such species is limited to a few specialised studies, hence the status of such species cannot be determined. Both sandy and shingle beaches receive substantial inputs of seagrass wrack, mainly Posidonia, during the autumn and winter months. Posidonia banquettes constitute a specific habitat type associated with the littoral shoreline, including rocky coastline, and are considered to be an important source of organic matter on Maltese beaches 49. A quantitative assessment of Posidonia wrack beached along Maltese coastline provided an estimate of metric tons (dry weight) of standing wrack per km of beach 50,51 with a maximum total dry mass of wrack beached along Maltese coastlines at any one time estimated at ca 1,150 metric tons 52. Given the transient nature of Posidonia banquettes which is easily affected by natural factors, including storms, they will not be considered any further for the purposes of MSFD assessment of environmental status. Other habitat types falling within the scope of the MSFD habitat type Littoral Sediment include saltmarshes (as per EUNIS Habitat type A2.5), or coastal lagoons as interpreted by the EU Habitats Directive (habitat code 1150) 53. This habitat type is restricted to a few pockets on the Maltese Islands, most of which have been Deidun, A. Azzopardi, M., Saliba, S. & Schembri, P.J Low faunal diversity on Maltese sandy beaches: fact or artefact? Estuarine, Coastal and Shelf Science 58S: Talitrids refer to two species: Talorchestia deshaysii and Talitrus saltator. Distinguishing between these two species proves difficult hence the use of the term Talitrids incorporating both. Deidun, A. Azzopardi, M., Saliba, S. & Schembri, P.J Low faunal diversity on Maltese sandy beaches: fact or artefact? Estuarine, Coastal and Shelf Science 58S: Deidun, A.; Galea Bonavia, F. & Schembri, P.J Distribution of Tylos spp. in the Maltese Islands and population dynamics of Tylos europaeus. Journal of Coastal Research, SI 57 (Proceedings of the 11 th International Coastal Symposium), Szczecin, Poland, ISBN Gauci, M.; Deidun, A. & Schembri, P.J Faunistic diversity of Maltese pocket sandy and shingle beaches: are these of conservation value? Oceanologia 47 (2) pp Deidun, A.; Saliba, S. & Schembri, P.J Quantitative assessment and physical characterisation of Posidonia oceanica wrack beached along the Maltese coastline. Biol.Mar. Mediterr., 18 (1): A mean mass of 27.3 kg ± 2.4 kg for 1 m 3 of air-dried wrack and a mean banquette depth of 0.5 m were used for the calculation; Deidun, A.; Saliba, S. & Schembri, P.J Quantitative assessment and physical characterisation of Posidonia oceanica wrack beached along the Maltese coastline. Biol.Mar. Mediterr., 18 (1): European Commission, DG Environment Interpretation Manual of European Union Habitats 24

25 significantly engineered or altered by anthropogenic interference or disturbance 54. While the connection of these sites to the marine environment has been retained 55 through culverts (Il-Ballut, Marsaxlokk), pipelines (Il-Magħluq, Marsaskala) or through natural seepage of the adjacent seawater, such connection is largely artificial. In this regard, this type of habitat is not being considered further for the purposes of the MSFD. Nevertheless, all extant coastal lagoons are included in Special Areas of Conservation as designated within the framework of the Habitats Directive and will thus be managed and conserved for the purposes of this Directive. Further information regarding range, area and status of this habitat type can be found at: xml/manage_document, Figure 5: Location of sandy and shingle beaches representing Littoral Sediment for the Maltese Islands (Source: MEPA) Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 In line with the document entitled Links between the Marine Strategy Framework Directive (MSFD 2008/56/EC) and the Nature Directives (Birds Directive 2009/147/EEC (BD) and Habitats Directive 92/43/EEC (HD), coastal lagoons should only be considered under marine reporting if there is a permanent connection with the sea. 25

26 Pressures Beaches on the Maltese Islands constitute an important recreational resource. Due to the fact that they are restricted to small pockets along the shore, most beaches are subject to intense recreational use particularly during the summer season. Such recreational activities constitute the major threat to this habitat type and associated species. In view of the uniqueness of each beach in terms of species and the unclear relationships between species composition and abiotic factors, it is difficult to attribute difference in species composition to anthropogenic or natural factors. On the other hand, undisturbed beaches are generally associated with the highest number of sand-specific species, implying that human disturbance influences the macrofaunal species composition of a beach 56. The extent of the effect of anthropogenic disturbance on beach ecology is nevertheless unknown. In view of their recreational use, beaches are regularly cleaned. Although the degree of impact of such activity is largely dependent on the mechanisms used, it is considered to be a potential source of disturbance to the beach fauna. Furthermore, the removal of Posidonia banquettes from beaches may expose such beaches to erosion processes and potentially lead to a reduction in organic matter on the beaches. Deidun et al. (2007) 57 suggest that thick banquettes on ungroomed 58 beaches contribute more to beach biodiversity and to carbon cycling, while values of wrack percent organic matter content were estimated to be higher for ungroomed beaches 59. The significance of such difference in organic matter however is not known. The main pressure on the extent of beaches along the Maltese coastline arises from interferences with processes related to sand accretion and erosion, as a result of development on the coastline as well as development on land. Development on the coastline, such as the construction of jetties, would result in changes in the hydrodynamic regime of coastal waters which in turn may lead to erosion of sandy beaches. Development on land on the other hand would reduce the sediment supply from terrestrial valley systems. Both types of development have resulted in a reduction in the extent of a number of sandy beaches. Furthermore, these effects take place gradually over a long period of time and effects of past developments are still being observed to date and are expected to continue in the future. Given the already limited extent of Maltese pocket beaches, any reduction in their extent is deemed to be significant. While beach replenishment projects may have the opposite effect, hence an increase in the extent of beaches, such projects would 56 Deidun, A. & Schembri, P.J Long or short? Investigating the effect of beach length and other environmental parameters on macrofaunal assemblages of Maltese pocket beaches. Estuarine, Coastal and Shelf Science. 79: Deidun, A.; Saliba, S. & Schembri, P.J Banquette faunal assemblages from groomed and ungroomed beaches on the Maltese Islands. Rapp. Comm. Int. Mer Medit., 38: pp Beaches which are not regularly cleaned 59 Deidun, A.; Saliba, S. & Schembri, P.J Quantitative assessment and physical characterisation of Posidonia oceanica wrack beached along the Maltese coastline. Biol. Mar. Mediterr. 18 (1):

27 generally have a negative effect on the beach biota (J.A. Borg & P.J. Schembri, personal communication) Shallow sublittoral rock and biogenic reef Communities of infralittoral algae, together with Posidonia oceanica meadows on rock are considered to be the most important communities in terms of cover on shallow rocky bottoms from 0-30m depth 60. Posidonia oceanica meadows will be described in further detail with the shallow sublittoral sediment. Figure 6 depicts the distribution of communities associated with shallow sublittoral rock based on available data. Such data constitutes snapshot data and does not cover the whole extent of this substrate type in Malta 61. However, an indication of the presence of rocky substrata in shallow waters is provided in Figure 7, which data is extracted from the results of a side-scan sonar survey carried out in Given the current data limitations, only a generic description of this habitat type as extracted from published literature is possible at this stage. A general description of the different biotopes associated with sublittoral rock is given by Pirotta et al. (1997) 63 as follows: Sublittoral rock characterised by sloping bedrock extending for a considerable distance out to sea: such slopes can be further subdivided into gentle and steep slopes dominated by photophilic macroalgae, mainly phaeophytes in shallow waters with chlorophytes becoming more important with increasing depth. Underwater cliff faces or drop-offs which can be continuous vertical slopes or stepped with ledges and breaks across their face: the biota of drop-offs depends on the topography of the substratum but generally consists of photophilic macroalgae overlying a sciaphilic assemblage of encrusting sponges, corals, hydroids and bryozoans. Sciaphilic assemblages dominate in low light conditions either beneath ledges or in rock crevices 64. Boulder fields which are characterised by detached fragments of rock >50cm in diameter over an extensive slope: this type of seabed is very heterogeneous and is characterized by continuously changing depth and light intensity depending on the arrangement of the individual boulders. The biota of boulder fields consists of assemblages dominated by photophilic macroalgae in high light intensity and Borg J. A., Micallef S. A., Pirotta K., Schembri P. J., Baseline marine benthic surveys in the Maltese Islands (Central Mediterranean). In E. Ozhan (ed.) Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST ë97, November 11-14, 1997, pp v figs. The distribution map was created through an amalgamation of the current snapshot data. Overlapping data was addressed through selection of the most recent and/or higher resolution data. G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp Pirotta, K. & Schembri, P.J Characterisation of the Major Marine Biotopes occurring around the Maltese Islands: Biotopes of Hard Substrata. In: E. Ozhan (ed). Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST 97, November Pirotta, K. & Schembri, P.J Characterisation of the Major Marine Biotopes occurring around the Maltese Islands: Biotopes of Hard Substrata. In: E. Ozhan (ed). Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST 97, November

28 by sciaphilic assemblages consisting mainly of encrusting species in low light conditions 65. Due to the tilting of the Maltese Islands to the Northeast, the North-eastern coast is characterised by gently sloping rocky seabed mainly exploited by communities of photophilic algae and in some areas by P. oceanica meadows settled on rock 66. Most of the Southwestern coast of the Maltese Islands is on the other hand characterised by cliffs and boulder fields occurring at the base of the vertical faces, supporting extensive communities of macroalgae. Since relatively large depths are generally reached within small horizontal distances (5-200m) from the shoreline, these communities of photophilic algae consist mainly of sciaphilic assemblages. Seagrass meadows are rarely encountered in these sites 67. Algal communities characterising infralittoral rock include those dominated by the phaeophytes Cystoseira species in shallower waters, including Cystoseira amentacea var. stricta which assemblage has also been described for the lower mediolittoral zone. Other Cystoseira species characterising the infralittoral of Malta include C. brachycarpa, C. spinosa, C. compressa and C. ercegovicii 68. Other algal species which when in dominance constitute specific benthic associations include the phaeophytes Sargassum vulgare, Dictyopteris polypodioides, Halopteris scoparia, Padina pavonica and Zonaria tourneforti; the chlorophytes Dasycladus vermicularis, Flabellia petiolata, Cladophora prolifera, Acetabularia acetabulum and Caulerpa racemosa; and the rhodophytes Peyssonnelia squamaria and Halopithys pinastroides 69. Some assemblages occur in polluted areas particularly ports and harbours such as the association with Dictyota dichotoma and Halimeda tuna, the association with Cladophora prolifera and the association with Corallina elongata and Amphiroa sp. 70. The same applies to the alga Enteromorpha (=Ulva) linza which colonises the mediolittoral and upper infralittoral zone in polluted waters and may be an indicator of nutrient enrichment Pirotta, K. & Schembri, P.J Characterisation of the Major Marine Biotopes occurring around the Maltese Islands: Biotopes of Hard Substrata. In: E. Ozhan (ed). Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST 97, November Borg J. A., Micallef S. A., Pirotta K., Schembri P. J., Baseline marine benthic surveys in the Maltese Islands (Central Mediterranean). In E. Ozhan (ed.) Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST ë97, November 11-14, 1997, pp v figs. Borg J. A., Micallef S. A., Pirotta K., Schembri P. J., Baseline marine benthic surveys in the Maltese Islands (Central Mediterranean). In E. Ozhan (ed.) Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST ë97, November 11-14, 1997, pp v figs. Borg, J.A. & Schembri, P.J., 2002 Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 ditto ditto Galdies, C. & Borg, J.A Aerial Remote Sensing and Spatial Analysis of Marine Benthic Habitats in St George s Bay (Malta); 2nd International Conference on the Management of Coastal Recreational Resources Beaches, Yacht Marinas and Coastal Ecotourism; Gozo, Malta;

29 Faunal species characteristic of infralittoral rock include 72 : the sponge Chondrilla nucula associated with well-lit conditions, Astroides calycularis common in shady conditions, Dendropoma/Neogoniolithon trottoirs occurring at sea level and the uppermost reaches of the infralittoral, Serpulorbis arenaria occurring on exposed rock in shallow water. Cladocora caespitosa which forms small colonies not more than 15cm in diameter. No reefs (or continuous cover of colonies) are formed however 73,74. Localised surveys describe communities on shallow sublittoral rock which may represent enclaves of deeper water communities. These communities were recorded within shallow caves and on shaded vertical rock faces at relatively shallow depths not exceeding 42m 75,76. This habitat type is characterised by encrusting algae (including Peyssonnelia squamaria recorded in the Filfla area and Lithophyllum frondosum in association with Zonaria tournefortii recorded at the mouth of caves in the Dwejra area), encrusting and erect bryozoans (including Myriapora truncata, Caberea boryi, Smittina cervicornis and possibly Celleporina caminata and Schizoporella species), corals (Leptosammia pruvoti), several species of sponges (including Agelas oroides, Petrosia ficiformis, Faciospongia cavernosa, Buskea dichotoma and Chondrosia reniformis), the ascidian (Halocynthia papillosa) and hydroids of the genus Eudendrium sp. With the exception of Peyssonnelia squamaria, species mentioned above are considered to be characteristic of coralligene or coralligenous communities (vide Ballesteros 2006) 77. Some vagile fauna recorded is also considered to be associated with coralligenous communities such as Centrostephanus longispinus and Ophidiaster ophidianus. More detailed studies would be required to determine whether the species assemblages constitute enclaves of coralligenous communities in shallow waters or otherwise. However, they almost certainly constitute pre-coralligene communities, which differ from coralligenous communities in terms of extent of concretion by coralline algae and other encrusting biota, and the cover of the latter (Schembri, P.J., personal communication) Borg, J.A. & Schembri, P.J., 2002 Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 Borg, J.A. & Schembri, P.J., 2002 Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34: 128 Borg, J.A.; Dimech, M. & Schembri, P.J Report on a survey of the marine infralittoral benthic habitats in the Dwejra/Qawra area (Gozo, Maltese Islands) made in August September Survey commissioned by Nature Trust and the Malta Environment and Planning Authority AIS Environmental Ltd. & Malta Environment and Planning Authority Marine Scientific Surveys around Filfla for its conservation. Acoustic and Video Report, September Structural Funds Programme Malta Ballesteros, E Mediterranean Coralligenous Assemblages: A synthesis of present knowledge. Oceanography and Marine Biology: An Annual Review, 2006, 44,

30 Figure 6: Distribution of Shallow Sublittoral Rock in Malta (Sources: Borg & Schembri, , Borg et al., , Borg et al ; ADI Associates & Scott Wilson, ) Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs 1-23 Borg, J.A.; Dimech, M. & Schembri, P.J Report on a survey of the marine infralittoral benthic habitats in the Dwejra/Qawra area (Gozo, Maltese Islands) made in August September Survey commissioned by Nature Trust and the Malta Environment and Planning Authority Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2); ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority. 30

31 Figure 7: Indication of rocky substrata as identified through the 2002 side-scan sonar (Source: G.A.S ). Pressures Nutrient enrichment is considered to be one of the major pressures on shallow sublittoral rock communities (J.A. Borg & P.J. Schembri, personal communication). This pressure is generally associated with sewage outfalls and overflows, port operations and agricultural runoff. Other pressures related to human activities in coastal waters, such as boating, could also be of significance to this habitat type 83. Temporary marinas, fisheries berthing areas and boating activities in general are associated with a chronic input of contaminants in coastal waters, thus leading to a reduction in water quality. However, the extent of such pressures on shallow sublittoral rock is unknown. On the other hand, vulnerable communities which occur on shallow sublittoral rock such G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp Borg J. A., Micallef S. A., Pirotta K.. & Schembri P. J., Baseline marine benthic surveys in the Maltese Islands (Central Mediterranean). In E. Ozhan (ed.) Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST ë97, November 11-14, 1997, pp v figs. 31

32 as Cladocora caespitosa colonies are threatened by mechanical damage from the use of heavy anchors and fishing gear 84. Land-based discharges, such as brine discharges from desalination plants and cooling waters from power plants, and aquaculture (particularly when fish cages are located very close to shore) may also lead to reduced water quality with associated impacts on benthic communities characterising shallow sublittoral rock. Nevertheless, such pressures and associated impacts are considered to be localised. 84 Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34:

33 1.3.4 Shallow sublittoral sediment Posidonia oceanica meadows Benthic communities associated with shallow sublittoral sediment in Malta are those of bare well-sorted sands and seagrass meadows. In terms of cover, Posidonia oceanica meadows constitute the most important seagrass meadows that exploit shallow sandy substrata, and to a lesser extent, hard bottoms (Figure 8). P. oceanica meadows can also be characterised by a high matte composed of sediment and densely packed rhizomes which may reach a height of several metres 85. Seagrass beds can also be dominated by Cymodocea nodosa, however current data on the distribution of this assemblage is limited and would not reflect the actual range and extent of the habitat. In general, Cymodocea nodosa occurs throughout the infralittoral at depths less than 1m down to about 45-48m and are best developed on muddy sand bottoms 86. The Lessepsian immigrant Halophila stipulacea may also occur on fine sands, generally in association with C. nodosa up to a depth of 32m. However this is locally rare. P. oceanica meadows and assemblages associated with Cymodocea nodosa are listed in Annex I of the Habitats Directive (habitat codes 1120 and 1110 respectively) 87. In general all seagrass assemblages are considered to be important marine habitats in view of their high productivity. Posidonia meadows in particular provide a highly heterogeneous species-rich habitat which is associated with a wide range of ecosystem services through the provision of physical refuge and food for a number of marine biota, support to commercial fisheries through their role as nurseries as well as protection of the shore from wave action and coastal erosion 88,89. In 2002, MEPA commissioned a survey to determine the extent of P. oceanica meadows in Malta 90. The results of this side-scan sonar survey are used as the major source of information on P. oceanica meadows and as baseline data. However it Pirotta, K. & Schembri, P.J Characterisation of the Major Marine Biotopes occurring around the Maltese Islands: Biotopes of Soft Substrata. In: E. Ozhan (ed). Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST 97, Nov Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs Borg, J.A. (1998) Habitat Characteristics and fauna of Posidonia oceanica meadows in the Maltese Islands in Dandria, D (ed) Biology Symposium Biological Abstracts MSc, PhD and contributions to Marine Biology; Department of Biology, University of Malta. Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34: 128 G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp 33

34 should be noted that while it provides a general indication of the distribution of these meadows in Malta, there are inaccuracies, which any quantitative estimates based on this survey should acknowledge. Of particular note is the limited recognition by the side-scan sonar of P. oceanica meadows growing on rock, which thus could be more extensive than indicated by this survey (J.A. Borg & P.J. Schembri, personal communication). Such inaccuracies were confirmed by Borg et al. (2009) 91, who noted discrepancies between the GAS/MEPA data and the map of the large-scale distribution of P. oceanica meadows based on distribution data collected from various studies. For the purposes of this report, the data of the side-scan sonar was supplemented by either published data 92 or by data generated through localised surveys 93. Posidonia oceanica meadows are concentrated along the North-eastern coast of the Maltese Islands, covering a length of coastline of about 40.5km with a break of about 5.4km across the harbour areas. Along the Southwestern coast, P. oceanica oceanica covers about 12.8km of the coastline 94. The range and area of P. oceanica meadows as reported in 2007 as part of the requirements of the Habitats Directive, are 172km 2 and 168km 2 respectively 95. Within this coverage, the distributional pattern of P. oceanica meadows varies from continuous meadows to reticulate or patchy meadows with intermittent patches of sand or rock 96. However, the species richness, abundance and assemblage composition of macroinvertebrates does not seem to differ significantly between non-fragmented and fragmented beds of Posidonia oceanica 97. The general distribution pattern of this habitat type as extrapolated from four locations studied by Borg et al. (2009) 98 is: patchy in shallow waters (2-4m) mainly occurring on bedrock, reticulate beds consisting of P. oceanica growing on a soft sediment bottom and interspersed with bare sand in deeper waters (5-10m), continuous beds up to a depth of 25-30m and Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2); ditto High resolution data generated by localised surveys was superimposed on the side-scan sonar data. In areas of overlap, the side-scan sonar data was replaced by the higher resolution data. Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2); Calculations are based on a grid-based approach as per European Topic Centre on Biological Diversity (2011) Assessment and reporting under Article 17 of the Habitats Directive: Explanatory notes & Guidelines for the period Final Draft. Pirotta, K. & Schembri, P.J Characterisation of the Major Marine Biotopes occurring around the Maltese Islands: Biotopes of Soft Substrata. In: E. Ozhan (ed). Proceedings of the third international conference on the Mediterranean coastal environment, MEDCOAST 97, Nov Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. & Jones, M.B Spatial variation in the composition of motile macroinvertebrate assemblages associated with two bed types of the seagrass Posidonia oceanica. Marine Ecology Progress Series 406: Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2);

35 reticulate again in deeper waters. Posidonia oceanica meadows occur up to a maximum depth of 44m, a depth at which this type of assemblage is only rarely recorded in Mediterranean waters 99. Figure 8: Distribution of Posidonia oceanica meadows in Malta (Sources: Borg & Schembri, , Borg et al , G.A.S ; ADI Associates & Scott Wilson, ; Micallef et al ) 99 Borg, J.A. (1998) Habitat Characteristics and fauna of Posidonia oceanica meadows in the Maltese Islands in Dandria, D (ed) Biology Symposium Biological Abstracts MSc, PhD and contributions to Marine Biology; Department of Biology, University of Malta. 100 Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs Borg, J.A.; Dimech, M. & Schembri, P.J Report on a survey of the marine infralittoral benthic habitats in the Dwejra/Qawra area (Gozo, Maltese Islands) made in August September Survey commissioned by Nature Trust and the Malta Environment and Planning Authority 102 G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp 103 ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority. 104 Micallef, A.; Foglini, F.; LeBas, T.; Angeletti, L.; Maselli, V.; Pasuto, A. & Taviani, M The submerged paleolandscape of the Maltese Islands: Morphology, evolution and relation to Quaternary environmental change. Marine Geology. 335:

36 Species typical of this habitat type and which have been specifically studied in Malta include the Noble Pen Shell Pinna nobilis which is listed in Annex IV of the Habitats Directive 105. Such studies were carried out in four study areas located within Marine Protected Areas declared through Government Notice 851 of The surveys were carried out in January and February 2012 as a follow-up of a population assessment carried out in December 2006 in one of the protected areas. The population abundance of this species was low at all four study sites (c. 0.2 individuals/100m 2 ) which implies a significant decrease in abundance from 2006 (c. 1.8 individuals/100m 2 ). The mean age of the population studied is about 2 years. The abundance of young individuals implies an unstable population with high mortality rate. Further assessments are currently being undertaken to assess the conservation status of this species in Malta, and possible reasons for decline. Other typical species include the echinoderm Paracentrotus lividus which is listed in the Bern Convention, SPA and Biodiversity Protocol as well as LN 311 of 2006 (as amended) as a species whose taking in the wild and exploitation may be subject to management measures. Research is required to elucidate current exploitation levels of P. lividus, although the species is not considered threatened in the Maltese Islands. Pressures: Assemblages on shallow sublittoral sediment are subject to various anthropogenic pressures, both land-based and sea-based, mainly as a consequence of the concentration of anthropogenic activities in coastal waters. Bare sediments of the shallow sublittoral are subject to physical damage and nutrient enrichment, both of which may lead to changes in the composition or characteristics of the substrate. Activities which exert such pressures on this habitat type include aquaculture which is generally associated with nutrient enrichment, leading to changes in sediment characteristics, and with disturbance of such sediments through cage moorings (J.A. Borg & P.J. Schembri, personal communication). Intense recreational activities in Maltese bays during the summer months are also considered to be important sources of pressures on this habitat type. This particularly applies to boating activities in innermost parts of bays, causing disturbance of the sediment through moorings and anchoring. On a localised scale, the sinking of vessels as diving attractions and dumping of spoil in the marine environment are associated with impacts on this habitat type (J.A. Borg & P.J. Schembri, personal communication). Vessels are generally sunk on bare sand intentionally with a view to avoid impacts on the biodiversity-rich seagrasses, while dumping of solid waste should only take place within a designated spoil ground. The extent of impacts associated with the above-mentioned pressures on bare sands is 105 Ecoserv 2012 Study on the Noble Pen Shell (Pinna nobilis) populations in three Marine Protected Areas in Malta: marine area between Rdum Majjiesa to Ras ir-raheb; marine area in the limits of Mgarr ix-xini (Gozo) and marine area in the limits of Dwejra (Gozo). MEPA call for tenders: T 04/

37 not known. However the dynamic nature of this habitat type should be taken into consideration when assessing extent of impacts, including its potential for recovery. Assessments of impacts on Posidonia oceanica meadows have been carried out on localised areas, rendering quantification of such impacts at a National scale difficult. While not directly exploited, this habitat type is known to be potentially significantly affected by anchoring and deployment of moorings, aquaculture, dredging, discharges, particularly cooling waters from power plants and terrestrial runoff 106. In line with EC Regulation 1967 of , the use of towed fishing gears on seagrass meadows is prohibited. However these meadows can be affected by other types of fishing taking place on P. oceanica meadows such as trammel nets and fish traps (J.A. Borg & P.J. Schembri, personal communication). The extent of impact of such fishing activities on P. oceanica meadows is not known.. Pressures from moorings and anchoring are mainly expected within enclosed bays and other areas which are frequented by pleasure boats 108. Moorings and anchoring can result in impacts related to physical loss as well as interference with hydrological processes. Although the impacts of anchoring are widely known 109, this pressure cannot be quantified locally in view of the fact that, with the exception of one anchoring zone designated on a yearly basis in Comino, there is no official designation of anchoring zones or no-anchoring zones in the rest of Malta. On the other hand, studies related to beach replenishment projects in St. George s Bay (Malta) attributed lower shoot densities of P. oceanica to anthropogenic disturbance, including anchoring and moorings 110. Studies on one of the typical species associated with Posidonia oceanica meadows, Pinna nobilis, carried out within Marine Protected Areas at Rdum Majjiesa Ras ir-raheb, the marine area off Mgarr ix-xini (Gozo) and the marine area in Dwejra also refer to the potential impacts of anchoring on such species within these areas 111. With respect to reduction in water quality, historically, P. oceanica meadows are known to have regressed and been totally replaced by pollution tolerant benthic communities within harbours 112. Shipping and port-related activities, particularly 106 Schembri, P.J. (1995): Threatened habitats as a criterion for selecting coastal protected areas in the Maltese Islands. Rapport du Congres de la Commission Internationale pour l Exploration Scientifique de la Mer Mediterranee 34: Council Regulation 1967 of 2006 concerning management measures for the sustainable exploitation of fishery resources in the Mediterranean Sea 108 Borg, J.A. & Schembri P.J. (1995): The state of Posidonia oceanica (L.) Delile meadows in the Maltese Islands (Central Mediterranean); Rapp Comm int Mer Medit 34 p Garcia-Charton, J.A.; Pérez-Ruzafa, A; Marcos, C.; Claudet, J; Badalamenti, F; Benedetti-Cecchi, L; Falcón, JM; Milazzo, M; Schembri, PJ; Stobart, B; Vandeperre, F; Brito, A; Chemello, R.; Dimech, M.; Guala, I; Le Diréach, L; Maggi, E. & Planes, S. (2008) Effectiveness of European Atlanto-Mediterranean MPAs: do they accomplish the expected effects on populations, communities and ecosystems? Journal for Nature Conservation 16: Borg, J.A.; Gauci, M.J.; Magro, M. & Micallef, M Environmental Monitoring at St George s Bay (Malta) in connection with Beach Replenishment Works 2nd International Conference on the Management of Coastal Recreational Resources Beaches, Yacht Marinas and Coastal Ecotourism th October 2006, Gozo, Malta. 111 Ecoserv 2012 Study on the Noble Pen Shell (Pinna nobilis) populations in three Marine Protected Areas in Malta: marine area between Rdum Majjiesa to Ras ir-raheb; marine area in the limits of Mgarr ix-xini (Gozo) and marine area in the limits of Dwejra (Gozo). MEPA call for tenders: T 04/ Borg, J.A. & Schembri P.J. (1995): The state of Posidonia oceanica (L.) Delile meadows in the Maltese Islands (Central Mediterranean); Rapp Comm int Mer Medit 34 p123 37

38 dredging within ports, are also known to have significant impacts on P. oceanica meadows through physical loss and damage, the latter as a result of sediment resuspension and associated increase in turbidity. Bunkering activities may also exert pressures on Posidonia oceanica meadows through the anchoring of large vessels and generation of turbulence by such vessels (J.A. Borg & P.J. Schembri, personal communication). Although coastal eutrophication might not be a significant issue in Malta, and sewage outfalls which were previously known to affect this habitat type have been replaced with treated effluents 113, aquaculture exerts a significant pressure, albeit localised, on Posidonia through nutrient enrichment, shading (by the cages) and deployment of cage moorings. A case study in this regard follows from the establishment of fish farm cages in 1991 at a depth of 12-16m. The fish farm in question, which has now ceased operation, pre-dated current permitting systems.. In this case, the meadows directly beneath the cages were decimated and the meadow structure (shoot density, leaf area index and shoot biomass) was considerably altered in the vicinity of the cages 114. These changes were attributed to the elevated nutrient levels and high sedimentation rates near the cages, which led to a high epiphytic cover of the leaves, causing a reduction in the light intensity reaching the photosynthetic tissues, possibly limiting photosynthesis and potentially causing death of the plant due to a reduced oxygen flux from the leaves to the below-ground organs 115. These effects were noticed up to a distance of 200m. Borg et al. (2006) imply recovery of P. oceanica meadows following cessation of fish farm operation through a significant increase in shoot density 116. Current permitting processes are geared towards preventing such impacts 117. Within this context, reference is hereby being made to the aquaculture strategy for Malta (2012) 118. Coastal development is also known to have resulted in changes in hydrographical conditions and caused regression of seagrass meadows. A beach replenishment event which took place in 1990 following deposition of dredged marine sediment onshore (Birżebbuġa Bay) has resulted in the complete degradation of P. oceanica meadows through the movement of the sediment by wave action and currents offshore 119. Beach replenishment does not necessarily imply such degradation, indeed,monitoring surveys within a site, St. George s Bay, subject to a more recent 113 Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2); Dimech, M.; Borg, J.A. & Schembri, P.J Changes in the structure of a Posidonia oceanica meadow and in the diversity of associated decapod, mollusc and echinoderm assemblages, resulting from inputs of waste from a marine fish farm (Mata, Central Mediterranean). Bulletin of Marine Science 71(3): Dimech, M., Borg, J.A. & Schembri, P.J. (2000): Structural changes in a Posidonia oceanica meadow exposed to a pollution gradient from a marine fish farm in Malta (Central Mediterranean). Biol. Mar. Medit. 7 (2): Borg J. A., Micallef M. A, & Schembri P. J., Spatio-temporal variation in the structure of a deep water Posidonia oceanica meadow assessed using non-destructive techniques. Marine Ecology 27: Borg, J.A. & Schembri, P.J Changes in marine benthic community types in a Maltese Bay following beach replenishment works. Clean Seas Conference Proceedings 9-11 November 1993, Mediterranean Conference Centre, Valletta, Malta. 38

39 and better planned beach replenishment project indicated that the overall state of health of the seagrass (P. oceanica and C. nodosa) meadows appeared to have remained unchanged following beach replenishment 120. Localised impacts on P. oceanica meadows occur from various activities including the laying down of underwater cables and pipelines, discharges of cooling waters from power plants and discharges of brine from desalination plants. The laying down of cables and pipelines is considered to be a very localised one-time disturbance from which Posidonia oceanica meadows can recover (J.A. Borg & P.J. Schembri, personal communication. With respect to cooling water discharges, the impact of such discharge from the main power plant on the Maltese Islands on Posidonia has been established. Such impact is evident through an increased epiphytic growth, a regression in the extent of Posidonia and the replacement of the seagrass with Cymodocea nodosa and photophilic algal assemblages 121. In 2010 the rate of discharge of cooling waters was 295,000m 3 although an extension to the power plant is expected to increase this to 43,000m 3 /hr at 8 degrees above ambient. The effects of the discharge of cooling waters on the marine ecosystems in the area will be assessed annually as part of the environmental permit of the power plant. Shallow Sublittoral fine and coarse sediments Malta supports other benthic communities associated with shallow sublittoral sediment. Figure 9 provides an indication of the presence of fine and coarse sediments (excluding Posidonia oceanica meadows) as extracted from the 2002 side scan sonar surveys 122, while Figure 10 provides an indication of the distribution of benthic communities associated with shallow soft sediments identified through localised surveys. Communities associated with shallow sublittoral sediment include the biocoenosis of infralittoral stones and pebbles and the biocoenosis of infralittoral gravels as described by Borg & Schembri (2002) 123. Nevertheless, these communities need to be further studied and due to current data limitations they cannot be described or assessed for the purposes of the MSFD. 120 Galdies, C. & Borg, J.A Aerial Remote Sensing and Spatial Analysis of Marine Benthic Habitats in St George s Bay (Malta); 2nd International Conference on the Management of Coastal Recreational Resources Beaches, Yacht Marinas and Coastal Ecotourism; Gozo, Malta; AIS Environmental Ltd Alternative Assessment Report for the Disposal of Cooling Water Delimara Power Station 122 G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp 123 Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs

40 Localised data on infralittoral stones and pebbles at Dwejra (Gozo) indicates that such habitat types may be characterised by thin algal felt, supporting a rich macrofauna, the most abundant being the gastropods Gibbula spp. and Osilinus articulatus; the hermit crab Clibanarius erythropus; the Crabs Xantho poressa and Xantho incisus; and the porcelain crab Pisidia sp 124. A similar community was recorded on infralittoral stones and pebbles along the North-eastern coast of Malta 125. Biocoenosis of coarse sands and fine gravels mixed by waves in the Dwejra area were characterised by an impoverished epibiota (mainly by Holothuria spp.) but a rich infauna as evidenced by the presence of numerous openings to burrows of infaunal species. Although the current data scenario does not allow further elaboration on this habitat type, recent studies in relation to the gastropod Gibbula nivosa 126 revealed the possibility for this species to be associated with infralittoral cobbles and pebbles rather than solely with Posidonia oceanica meadows as previously thought 127. Evans et al. (2011) 128 indicate the possibility that this gastropod is only secondarily associated with seagrasses, with records on seagrasses attributed to foraging. These individuals would retreat to cobble/pebble habitat when not feeding. Live specimens of this gastropod had not been recorded in Malta for the past two decades and were only recently recorded at two localities in the Maltese Islands: off western Comino and within Marsamxett Harbour. The largest population was recorded within Marsamxett Harbour on a gently sloping bottom of gravelly sand and silt with overlying cobbles and pebbles at 5 12 m depth 129. Significantly higher densities of Gibbula nivosa were associated with the upper pebble stratum rather than with the underlying gravelly sand 130. The overall population size in Marsamxett Harbour was estimated around individuals in January 2008, however this population was subject to large temporal fluctuations in abundance 131. Two live individuals were also collected from a similar substrate type with sparser pebbles in Comino at a depth of 18-20m Borg, J.A., Dimech, M. & Schembri, P.J Report on a survey of the marine infralittoral benthic habitats in the Dwejra/Qawra area (Gozo, Maltese Islands), made in August September 2004; Survey commissioned by Nature Trust and the Malta Environment and Planning Authority. 125 ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority 126 Gibbula nivosa is listed in Annexes II and IV of the Habitats Directive; 127 Evans, J.; Borg, J.A. & Schembri, P.J Rediscovery of live Gibbula nivosa (Gastropoda: Trochidae); Rapp. Comm. int. Mer Médit., 39, Evans, J.; Borg, J.A. & Schembri, P.J. (2011) Distribution, habitat preferences and behaviour of the critically endangered Maltese top-shell Gibbula nivosa (Gastropoda, Trochidae). Marine Biology 158: Evans, J.; Borg, J.A. & Schembri, P.J Distribution, habitat preferences and behaviour of the critically endangered Maltese top-shell Gibbula nivosa (Gastropoda: Trochidae). Marine Biology 158: Evans, J.; Borg, J.A. & Schembri, P.J Rediscovery of live Gibbula nivosa (Gastropoda: Trochidae); Rapp. Comm. int. Mer Médit., 39, Evans, J., Borg, J.A. & Schembri, P.J Biology and conservation status of the endemic Maltese top-shell Gibbula nivosa (A. Adams, 1851) (Trochidae). Tentacle Evans, J.; Borg, J.A. & Schembri, P.J Rediscovery of live Gibbula nivosa (Gastropoda: Trochidae); Rapp. Comm. int. Mer Médit., 39,

41 Evans et al. (2011) 133, 134 indicate an estimated extent of occurrence of this species as less than 100km 2 while its area of occupancy is less than 10km The population is also deemed to be fragmented given that the species is only known from a single site at each of the two localities. Furthermore, populations in sites where it was recorded in the past have not been recently observed and Gibbula nivosa may have become extinct within these sites. In this regard, this gastropod is considered to be critically endangered under the IUCN (2001) criteria 136. Benthic habitats associated with shallow sublittoral mud and/or mixed sediments have not been studied in enough detail to enable the assessment of status as per MSFD requirements. In general, muddy substrates characterise enclosed harbour areas along the Maltese coastline. Such muds are known to support assemblages dominated by Cymodocea nodosa or Halophila stipulacea 137. However these areas are considered to be highly disturbed by the harbour activities. Mixed sediments composed of gravely muddy sands are also associated with the presence of Cymodocea nodosa and Spatangus purpureus or Caulerpa racemosa. 133 Evans, J.; Borg, J.A. & Schembri, P.J Distribution, habitat preferences and behaviour of the critically endangered Maltese top-shell Gibbula nivosa (Gastropoda: Trochidae). Marine Biology 158: Evans, J., Borg, J.A. & Schembri, P.J Biology and conservation status of the endemic Maltese top-shell Gibbula nivosa (A. Adams, 1851) (Trochidae). Tentacle Evans, J.; Borg, J.A. & Schembri, P.J Distribution, habitat preferences and behaviour of the critically endangered Maltese top-shell Gibbula nivosa (Gastropoda: Trochidae). Mar Biol 158: Evans, J.; Borg, J.A. & Schembri, P.J Distribution, habitat preferences and behaviour of the critically endangered Maltese top-shell Gibbula nivosa (Gastropoda: Trochidae). Mar Biol 158: Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs

42 Figure 9: Presence of fine and coarse sediments (excluding Posidonia oceanica meadows) in shallow waters as identified through a side-scan sonar survey carried out in G.A.S. [Geological Assistance & Services] Baseline survey of the extent and character of Posidonia oceanica (L.) Delile meadows in the territorial waters of the Maltese Islands. Final Report. Geological Assistance & Services s.r.l. (G.A.S.) Bologna, Italy, iii + 176pp 42

43 Figure 10: Distribution of communities associated with Shallow Sublittoral Sediment in Malta (Sources: Borg & Schembri, , Borg et al ; ADI Associates & Scott Wilson, ) Shelf sublittoral rock and biogenic reef Benthic communities associated with shelf sublittoral rock are poorly known in Malta. Some data originates from localised surveys including a description of an expanse of barren rock at a depth of circa 120m in the marine area of the islet of Filfla, off the southwestern coast of Malta (Figure 11). This stretch of seabed supports tall hydroids possibly of the species Nemertesia ramosa. However, there are relatively few studies which describe this type of habitat and such data scenario precludes the possibility for assessing the extent of the communities associated with shelf sublittoral rock. 139 Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs Borg, J.A.; Dimech, M. & Schembri, P.J Report on a survey of the marine infralittoral benthic habitats in the Dwejra/Qawra area (Gozo, Maltese Islands) made in August September Survey commissioned by Nature Trust and the Malta Environment and Planning Authority 141 ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority. 43

44 This substrate type in the Mediterranean is known to support coralligenous biocoenosis described as two main types of assemblages: Lithophyllo-Halimedetum tunae and Rodriguezelletum straforelloi 142. The presence of these assemblages has not been specifically reported for Malta, although they are known to occur at depths between m in the Siculo-Tunisian region 143. The depth at which such assemblages occur depend on the light intensity. The closest description of a benthic habitat which may fit within the definition of coralligenous communities originates from localised marine surveys within shallow caves and on shaded vertical rock faces at relatively shallow depths not exceeding 42m. These communities were briefly described in previous sections. Records of the occurrence of species which are typical of such communities in Malta do exist, albeit the data available is very scant. Corallium rubrum is one such species which has been identified in Malta and has been recently observed at depths between 585m and 819m 144. Very little is known about the distribution and status of Corallium rubrum at intermediate depths (60-300m) 145. Corallium rubrum has been commercially harvested since ancient times for its red axial calcitic skeleton 146. Historical data indicates that this species was fished between the period at around depths of m 147, however such exploitation has now ceased. This species is strictly protected and trade of this species is illegal 148. Pressures: Although the pressures on this habitat type have not been documented, it is not expected to be subject to any significant pressure. Some species associated with shelf sublittoral rock, such as Corallium rubrum may also be subject to exploitation, however this activity does not take place any longer and presumably the population of such species should be recovering from past overexploitation. 142 Ballesteros, E Mediterranean Coralligenous Assemblages: A synthesis of present knowledge. Oceanography and Marine Biology: An Annual Review, 2006, 44, Ballesteros, E Mediterranean Coralligenous Assemblages: A synthesis of present knowledge. Oceanography and Marine Biology: An Annual Review, 2006, 44, Taviani, M.; Freiwald, A.; Beuck, L.; Angeletti, L.; Remia, A.; Vertino, A.; Dimech, M. & Schembri, P.J. (2010): The deepest known occurrence of the precious red coral Corallium rubrum (L. 1758) in the Mediterranean Sea in Bussoletti, E., D. Cottingham, A. Bruckner, G. Roberts, and R. Sandulli (editors) Proceedings of the International Workshop on Red Coral Science, Management, and Trade: Lessons from the Mediterranean. NOAA Technical Memorandum CRCP-13, Silver Spring, MD 233 pp. 145 Costantini, F.; Taviani, M.; Remia, A.; Pintus, E.; Schembri, P.J. & Abbiati, M Deep-water Corallium rubrum from the Mediterranean Sea: preliminary genetic characterisation. Marine Ecology 31: ditto 147 Deidun, A.; Tsounis, G.; Balzan, F. & Micallef, A Records of black coral (Antipatharia) and red coral (Corallium rubrum) fishing activities in the Maltese Islands. Marine Biodiversity Records, Marine Biological Association of the United Kingdom doi: /s ; Vol. 3; e90; 2010 Published online 148 The species is protected in the Maltese Islands since 1999, and is currently listed in Schedule VI (Animal and Plant species of National Interest in need of Strict Protection), and consequently covered by Regulation 25 of the Flora, Fauna and Natural Habitats Protection Regulations, 2006 (Legal Notice 311 of 2006 as amended). 44

45 Figure 11: Distribution of known assemblages belonging to the Shelf Sublittoral Rock & Biogenic Reef category (Sources: AIS Environmental Ltd. & MEPA, ; Dimech et al., ) 149 AIS Environmental Ltd. & Malta Environment and Planning Authority Marine Scientific Surveys around Filfla for its conservation. Acoustic and Video Report, September Structural Funds Programme Malta Dimech, M.; Borg J.A. & Schembri P.J. (2004) Report on a video survey of an offshore area off Zonqor Point (south-eastern coast of Malta), made in April 2004 as part of baseline ecological surveys in connection with the establishment of an aquaculture zone. Report I - Preliminary video characterization. [Survey commissioned by the Malta Environment and Planning Authority]. Msida, Malta: Malta University Services Ltd; pp 14 + Figs 1 4+video[2DVDs] 45

46 1.3.6 Shelf sublittoral sediment Shelf sublittoral sediments occupy a substantial extent of the seabed. Data collected by the Fisheries trawl surveys carried out annually on soft sediments between depths of m may shed light on the communities associated with shelf sublittoral sediment which are otherwise poorly documented in Malta. This analysis is currently being undertaken through collaboration between the University of Malta and the Fisheries Department, however it has not been finalised at the time of writing this document. Figure 12 provides an indication of the distribution of known benthic habitats which form part of the Shelf Sublittoral Sediment habitat category. In general, shelf sublittoral sediments within the m depth zone are characterised by sandy substrata, while at depths greater than 100m, muds would prevail. Published analysis of Fisheries data indicate that at depths between m the demersal fauna associated with shelf sublittoral sediment was dominated by commercial species of fish and cephalopods (in particular Mullus barbatus and Ilex coindetti) and non-commercial species in particular the crinoids Leptometra phalangium and Antedon mediterranea as well as juveniles of Parapaneus longirostris 151. High densities of Leptometra phalangium recorded through the trawl surveys is possibly also due to the aggregation of such species on the sides of trawling lanes to feed on the suspended sediments 152. Studies on sublittoral muds in open areas at depths between m indicate the absence of macroalgae and the presence of megafauna mainly represented by the echinoderms Stylocidaris affinis, Astropecten species, Spatangus purpureus and Antedon mediterranea as well as the occasional hermit crabs Pagurus sp. These sediments are also known to support a rich infauna as indicated by the observed burrows possibly belonging to polychaetes and crustaceans 153. Associations of coarse sediments with rhodoliths and maerl beds constitute better known benthic communities of the shelf sublittoral. These associations are characterised by accumulations of unattached coralline algae or rhodoliths (Corallinales, Rhodophyta) and occasionally calcified peysonneliacean algae 154. The term maerl beds is used when rhodoliths constitute a dominant proportion of the 151 Dimech, M.; Camilleri, M.; Gristina, M.; Kaiser, M.J. & Schembri, P.J , Commercial and non-target species of deep-water trawled muddy habitats on the Maltese continental shelf. Xjenza 10; p ditto 153 Dimech M., Borg J.A., Schembri P.J. (2004) Report on a video survey of an offshore area off Zonqor Point (south-eastern coast of Malta), made in April 2004 as part of baseline ecological surveys in connection with the establishment of an aquaculture zone. Report I - Preliminary video characterization. [Survey commissioned by the Malta Environment and Planning Authority]. Msida, Malta: Malta University Services Ltd; pp 14 + Figs 1 4+video[2DVDs] 154 Bordehore, C., Borg, J.A., Lanfranco, E., Ramos-Espla, A.; Rizzo, M.; Schembri, P.J. (2000): Trawling as a major threat to Mediterranean Maerl beds. Proceedings of the first Mediterranean Symposium on Marine Vegetation (Ajaccio, 3-4 October 2000) 46

47 sediment layer (P.J. Schembri, personal communication). All grades ranging from sparse rhodoliths to full maerl beds occur in Malta. In the Mediterranean, maerl beds occur in the transition zone between the lower infralittoral and upper circalittoral, although sparse rhodoliths occur at other depths 155,156. The depth limit depends primarily on the degree of light penetration and the high degree of light penetration in the Mediterranean can explain the common occurrence of live coralline algae at a water depth of 51-90m, which far exceeds most other maerl beds in the NE Atlantic 157. The major maerl bed in Malta covers an extent of circa 20km 2 of the seabed off the North-eastern coast of Malta at m depth 158. However accumulations of rhodoliths or unattached coralline algae were recorded from other areas: off the Southeastern coast of Malta up to a maximum depth of 85m recorded through a video survey as part of the Environmental Impact Assessment process. This study area was characterised by a sparse maerl bed in association with different types of substrata such as sand, cobbles and pebbles. Rhodoliths were mainly restricted to the relatively shallower areas (ca m) on a submarine plateau. In deeper areas (ca m), rhodolith associations were replaced by muddy sand without rhodoliths 159. Off the North-eastern coast of Malta at depths 45-50m recorded through a survey of two marine areas along the coast aimed at assessing the feasibility for land reclamation projects within these areas. This area was characterised by both maerl beds and associations with rhodoliths, with the former supporting the gorgonian Eunicella singularis in some places 160 ; Off the Southwestern coast of Malta on a raised bank between mainland Malta and the islet of Filfla 161. A recent study on the seafloor from offshore North Gozo to Southeastern Malta delineates a wide expanse of the seabed characterised by Maerl, sand and gravel Bordehore, C., Borg, J.A., Lanfranco, E., Ramos-Espla, A.; Rizzo, M.; Schembri, P.J. (2000): Trawling as a major threat to Mediterranean Maerl beds. Proceedings of the first Mediterranean Symposium on Marine Vegetation (Ajaccio, 3-4 October 2000) 156 ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority 157 Sciberras, M.; Rizzo, M.; Mifsud, J.R; Camilleri, K.; Borg, J.A.; Lanfranco, E.; & Schembri, P.J Habitat structure and biological characteristics of a maerl bed off the north-eastern coast of the Maltese Islands (central Mediterranean); Marine Biodiversity: 31: DOI /s ditto 159 Dimech, M.; Borg J.A. & Schembri PJ (2004) Report on a video survey of an offshore area off Zonqor Point (south-eastern coast of Malta), made in April 2004 as part of baseline ecological surveys in connection with the establishment of an aquaculture zone. Report I - Preliminary video characterization. [Survey commissioned by the Malta Environment and Planning Authority]. Msida, Malta: Malta University Services Ltd; pp 14 + Figs 1 4+video[2DVDs] 160 ADI Associates & Scott Wilson Detailed investigation and feasibility studies on Land Reclamation at two indicated search areas, Malta. Technical Report 1; Volume 1. Report prepared for Malta Environment and Planning Authority 161 AIS Environmental Ltd. & Malta Environment and Planning Authority Marine Scientific Surveys around Filfla for its conservation. Acoustic and Video Report, September Structural Funds Programme Malta

48 (Figure 13). Experts are of the opinion that the area indicated as maerl, sand and gravel through this study reflects the actual extent of shelf sublittoral coarse sediment with rhodoliths along the North-eastern and Southeastern coast of Malta, possibly representing all grades of coarse sediment with rhodoliths ranging from sediment with sparse rhodoliths to full maerl beds (J.A. Borg & P.J. Schembri, personal communication). In Malta maerl beds are characterised by five species of maerl forming algae: Lithothamnion minervae, Phymatolithon calcareum, Lithothamnion corallioides, Lithophyllum racemus and Mesophyllum alternans 163. Lithothamnion minervae was the most abundant rhodolith-forming species present at the maerl bed off the Northeastern coast of Malta. Neogoniolithon brassica-florida and Peysonnelia species may also occur at lower quantities 164. Maerl beds provide a substratum which is exploited by a wide variety of species typical of both hard and soft substrata. Faunal assemblages associated with maerl beds include 165 : burrowing and interstitial forms that utilize the sediment underlying the rhodoliths and the interstices between the rhodolith thalli; sessile epifaunal organisms that utilise the rhodoliths and the stabilised upper layer of sediment and vagile epifauna. The dominant faunal groups associated with maerl beds are annelids, crustaceans and molluscs, however most animal species within these taxonomic groups occur in other infralittoral and circalittoral habitats and are not restricted to maerl beds 166. Megafauna associated with maerl beds or associations with rhodoliths are generally characterised by the echinoderm Stylocidaris affinis and Astropecten species. 162 Micallef, A.; Foglini, F.; LeBas, T.; Angeletti, L.; Maselli, V.; Pasuto, A. & Taviani, M The submerged paleolandscape of the Maltese Islands: Morphology, evolution and relation to Quaternary environmental change. Marine Geology. 335: Lanfranco, E.; Rizzo, M.; Hall-Spencer, J.; Borg, J.A. & Schembri, P.J Maerl-forming coralline algae and associated phytobenthos from the Maltese Islands. The Central Mediterranean Naturalist 3(1): Lanfranco, E.; Rizzo, M.; Hall-Spencer, J.; Borg, J.A. & Schembri, P.J Maerl-forming coralline algae and associated phytobenthos from the Maltese Islands. The Central Mediterranean Naturalist 3(1): Sciberras, M.; Rizzo, M.; Mifsud, J.R; Camilleri, K.; Borg, J.A.; Lanfranco, E.; & Schembri, P.J Habitat structure and biological characteristics of a maerl bed off the north-eastern coast of the Maltese Islands (central Mediterranean); Marine Biodiversity: 31: DOI /s ditto 48

49 Figure 12: Distribution of known assemblages belonging to the Shelf Sublittoral Sediment category (Sources: Borg & Schembri, ; AIS Environmental Ltd. & MEPA, ; Dimech et al., ) 167 Borg, J.A. & Schembri, P.J. (2002) Alignment of marine habitat data of the Maltese Islands to conform to the requirements of the EU habitats directive (Council Directive 92/43/EEC). [Report Commissioned by the Malta Environment and Planning Authority]. Malta: Independent Consultants; 136pp + Figs AIS Environmental Ltd. & Malta Environment and Planning Authority Marine Scientific Surveys around Filfla for its conservation. Acoustic and Video Report, September Structural Funds Programme Malta Dimech, M.; Borg J.A. & Schembri P.J. (2004) Report on a video survey of an offshore area off Zonqor Point (south-eastern coast of Malta), made in April 2004 as part of baseline ecological surveys in connection with the establishment of an aquaculture zone. Report I - Preliminary video characterization. [Survey commissioned by the Malta Environment and Planning Authority]. Msida, Malta: Malta University Services Ltd; pp 14 + Figs 1 4+video[2DVDs] 49

50 Figure 13: Area characterised by Maerl, Sand and Gravel as indicated in Micallef et al.; Pressures The major pressure on Shelf sublittoral sediment is caused by trawling or other fishing activity. Fishing disturbance may cause shifts in the benthic community structure that particularly affect mobile scavenging species, which are probably the most food-limited trophic group on muddy seabeds. However, it must be pointed out that trawling within the Fisheries Management Zone is controlled as per EC Regulation 1967 of Maerl beds are fragile habitats occurring in localised areas within coastal areas and supporting many rare, unusual and scientifically interesting species 172. This coupled to the slow growth of rhodoliths implying slow recovery from perturbations, renders maerl beds highly susceptible to anthropogenic disruptions. Maerl beds are threatened by fishing activities, particularly trawling which can lead to physical and biological degradation of this benthic habitat Micallef, A.; Foglini, F.; LeBas, T.; Angeletti, L.; Maselli, V.; Pasuto, A. & Taviani, M The submerged paleolandscape of the Maltese Islands: Morphology, evolution and relation to Quaternary environmental change. Marine Geology. 335: Dimech, M.; Camilleri, M.; Hiddink, J.G.; Kaiser, M.J.; Ragonese, S. & Schembri, P.J Differences in demersal community structure and biomass size spectra within and outside the Maltese Fishery Management Zone (FMZ) Scientia Marina 72(4) December 2008, BIOMAERL Team 2001; Conservation and Management of NE Atlantic and Mediterranean maerl beds; International Workshop/Conference on The Scientific Basis for Conservation Management of Maerl Grounds 173 ditto 50

51 Maerl is considered to be very sensitive to suspended sediment, hence trawling and other activities such as aquaculture 174 and dredging are expected to impact on maerl beds through physical damage 175. On the other hand, given that the extent of maerl beds may actually be wider than presently known, level of impacts cannot be assessed at this stage Furthermore, it was clearly shown that fishing with set trammel nets on maerl beds leads to selective removal and mortality of large rhodoliths as they become entangled within the nets. The removal of the largest rhodoliths might lead to longterm shifts in maerl community structure in Malta, given their slow growth rate. Bunkering areas, some of which overlap with the presence of maerl beds are also considered to be a source of pressure since anchoring of large vessels would lead to physical damage of this habitat type (J.A. Borg & P.J. Schembri, personal communication). 174 In Malta, one of the tuna farms is located on the sparse maerl bed recorded off the Southeastern coast of Malta. 175 AIS Environmental Ltd. & Malta Environment and Planning Authority Marine Scientific Surveys around Filfla for its conservation. Acoustic and Video Report, September Structural Funds Programme Malta

52 1.3.7 Upper bathyal rock and biogenic reef Marine habitats on rock at this depth stratum are not well-known in Malta. Furthermore, detailed topographic data which could channel biological investigations to particular sites potentially supporting biotic assemblages on upper bathyal rock is limited. This depth stratum is surveyed as part of the fisheries trawl surveys, generally carried out on soft substrata. The information which is currently available was in fact generated by accidental collection of deep-water corals during fishery trawl surveys, which occurrence was subsequently corroborated through ROV surveys 176,177. During the 2003 MEDITS and GRUND cruises, a limited number of exploratory hauls were made on hard grounds off the southern to south-western coast of Malta. Live reef-building corals Lophelia pertusa and Madrepora oculata and the solitary coral Desmophyllum dianthus were collected from depths between 395m-617m. An ROV survey of an escarpment in the vicinity of the area from which corals were collected revealed the presence of M. oculata at depths m and to a lesser degree L. pertusa at depths m 178. The white coral community is associated with Corallium rubrum and other gorgonians. The presence of live Corallium rubrum colonies was also documented during a 2007 cruise (R V Urania MARCOS) in a depth range between 585m and 819m 179,180. Species associated with the white corals, which were either collected by the exploratory hauls or observed by the ROV surveys, include the solitary coral Desmophyllum dianthus, the symbiotic polychaete Eunice norvegica, and the bivalve species Spondylus gussonii and Asperarca nodulosa. Other species recorded include the echinoid Cidaris cidaris, the gastropod Coralliophilia richardi, and the crab Anamanthia rissoana, all of which seem to associate with living deep-water coral banks 181. In particular Coralliophilia richardi is strictly associated with Lophelia and very likely with Madrepora species Schembri, P.J.; Dimech, M.; Camilleri, M. & Page, R. (2007) Living deep-water Lophelia and Madrepora corals in Maltese waters (Strait of Sicily, Mediterranean Sea). Cahiers de Biologie Marine 48: Freiwald, A.; Beuck, L.A.; Ruggeberg, A.; Taviani, M.; Hebbeln, D. & R/V Meteor cruise M70-1 participants The white coral community in the central Mediterranean sea revealed by ROV surveys. Oceanography; 22 (1); ditto 179 Taviani, M.; Freiwald, A.; Beuck, L.; Angeletti, L.; Remia, A.; Vertino, A.; Dimech, M. & Schembri, P.J. (2010): The deepest known occurrence of the precious red coral Corallium rubrum (L. 1758) in the Mediterranean Sea in Bussoletti, E., D. Cottingham, A. Bruckner, G. Roberts, and R. Sandulli (editors) Proceedings of the International Workshop on Red Coral Science, Management, and Trade: Lessons from the Mediterranean. NOAA Technical Memorandum CRCP-13, Silver Spring, MD 233 pp. 180 Costantini, F.; Taviani, M.; Remia, A.; Pintus, E.; Schembri, P.J. & Abbiati, M Deep-water Corallium rubrum from the Mediterranean Sea: preliminary genetic characterisation. Marine Ecology 31: Schembri, P.J.; Dimech, M.; Camilleri, M. & Page, R. (2007) Living deep-water Lophelia and Madrepora corals in Maltese waters (Strait of Sicily, Mediterranean Sea). Cahiers de Biologie Marine 48: Taviani, M., Angeletti, L., Dimech, M., Mifsud, C., Freiwald, A., Harasewych, M.G., Oliverio, M Coralliophilinae (Gastropoda: Muricidae) associated with deepwater coral banks in the Mediterranean. Nautilus 123 (3),

53 Two other research cruises have been carried out in the area: MEDCOR 2009 and DECORS 2011 (P.J. Schembri, personal communication). The results of these cruises have not been published as yet, however Taviani et al. (2011) 183 indicate that a complete swath bathymetric mapping of the area covered by active coral growth on the escarpment has been completed through MARCOS 2007 and MEDCOR The same authors indicate that this escarpment is located within a critical sector of the Mediterranean Sea, under the influx of two major water masses, the superficial inflow of Modified Atlantic Water and the deep counterflow of the Levantine Intermediate Water. Historical records indicate the presence of black coral (Antipatharia) in the upper bathyal ( m), the distribution of which is however unknown to date 184. Black corals used to be exploited in Malta and according to Deidun et al. (2010) 185 fishing for black coral ceased for two main reasons: the great depths involved, making the use of coral dredging or netting necessary in order to access the coral populations, and the fact that coral dredges have been prohibited in the EU since Pressures: The coral communities described above are located on a near vertical escarpment which is not trawlable. Therefore, based on the current data available, these assemblages are not considered to be subject to significant anthropogenic pressures, since they are naturally protected by the benthic topography (P.J. Schembri, personal communication) Upper bathyal sediment The benthic assemblages associated with the upper bathyal are not well known in Malta and the only information which is available originates from Fisheries surveys. As stated previously, data generated through the Fisheries surveys is currently being analysed, however this analysis has not been finalised at the time of writing this document. Muddy sediments between m, within the 25 nautical mile Fisheries Management Zone are reported to support commercial species typical of deep 183 Taviani, M., Angeletti, B., Antolini, A., Ceregato, A., Froglia, C., Lopez Correa, M., Montagna, P., Remia, A., Trincardi, F. & Vertino, A Geo-biology of Mediterranean Deep-water coral ecosystems. Marine Research at CNR, National Research Council of Italy, Department of Earth and Environment, Volume DTA/ Deidun, A.; Tsounis, G.; Balzan, F. & Micallef, A Records of black coral (Antipatharia) and red coral (Corallium rubrum) fishing activities in the Maltese Islands. Marine Biodiversity Records, Marine Biological Association of the United Kingdom doi: /s ; Vol. 3; e90; 2010 Published online 185 Deidun, A.; Tsounis, G.; Balzan, F. & Micallef, A Records of black coral (Antipatharia) and red coral (Corallium rubrum) fishing activities in the Maltese Islands. Marine Biodiversity Records, Marine Biological Association of the United Kingdom doi: /s ; Vol. 3; e90; 2010 Published online 53

54 waters including the giant red shrimp (Aristeomorpha foliacea), the Norway Lobster (Nephrops norvegicus) and Blackmouth Catshark (Galeus melastomus). These commercial species are accompanied by other species which are not exploited in Malta such as decapod crustaceans Plesionika heterocarpus, Pasiphaea sivado and Sergestes corniculum 186. However the species composition varies with depth and these species are not necessarily representative of this habitat type 187. The ROV survey of an escarpment off the Southwestern coast of Malta indicated the presence of bathyal muds along the seabed adjacent to the near-vertical wall, on which sessile octocorals Isidella elongata and Funiculina quadrangularis were observed. These muds have been bioturbated by crustacean burrows and by grazing tracks of holothuroids and cidaroid echinoids 188. These species are typical of bathyal muds and the ROV survey confirmed the presence of these assemblages in deep waters. However at this stage, there is no further data which allows the characterisation of the benthic assemblages associated with this type of habitat type and although the sampling sites used for Fisheries surveys may provide an indication of the occurrence of such habitat type within Malta, the current data scenario is not deemed adequate to allow the determination of the extent and distribution of this habitat type and assessment of status. Pressures: In terms of pressures, this habitat type is subject to fishing activities, namely trawling for commercial species and possibly bottom long-lining. However, it should be pointed out that trawling within the Fisheries Management Zone is regulated in line with EC Regulation 1967 of 2006 hence the fishing pressure on this type of habitat within the Fisheries Management Zone would be less than that on the same habitats outside which are known to be characterised by lower abundances and biomass of commercial species 189. Furthermore, the effects of trawling are generally more pronounced on non-target species, with the commercial catches being less sensitive to a moderate level of trawling effort Dimech, M. Camilleri, M.;. Kaiser, M.J., Schembri, P.J Demersal Assemblages on deep water trawling grounds off the Maltese Islands: Management Implications; Comm. int. Mer Médit., Dimech, M.; Camilleri, M.; Hiddink, J.G.; Kaiser, M.J.; Ragonese, S. & Schembri, P.J Differences in demersal community structure and biomass size spectra within and outside the Maltese Fisheries Management Zone (FMZ). Scientia Marina, 72 (4): Freiwald, A.; Beuck, L.A.; Ruggeberg, A.; Taviani, M.; Hebbeln, D. & R/V Meteor cruise M70-1 participants The white coral community in the central Mediterranean sea revealed by ROV surveys. Oceanography; 22 (1); Dimech, M.; Camilleri, M.; Hiddink, J.G.; Kaiser, M.J.; Ragonese, S. & Schembri, P.J Differences in demersal community structure and biomass size spectra within and outside the Maltese Fisheries Management Zone (FMZ). Scientia Marina, 72 (4): Dimech, M.; Camilleri, M.; Gristina, M.; Kaiser, M.J. & Schembri, P.J , Commercial and non-target species of deep-water trawled muddy habitats on the Maltese continental shelf. Xjenza 10; p

55 The mooring blocks of Fish Aggregating Devices may also be a source of impact on this habitat type Pace, R.; Dimech, M. & Schembri, P.J. (2007) Distribution and density of discarded limestone slabs used in the traditional Maltese lampuki fishery. Rapport du Congrès de la Commission Internationale pour l'exploration Scientifique de la Mer Méditerranée 38:

56 1.4 Pressures and Impacts The first Water Catchment Management Plan 192 for the Maltese Islands identifies and discusses pressures on coastal waters, namely point sources of pollution from urban and industrial sources, diffuse sources from industrial sources and urban runoff, and hydromorphological alterations. The information provided in the Water Catchment Management Plan (WCMP) is applicable for the purposes of the MSFD. However it is worth noting that since the publication of the first WCMP, all municipal wastewater is being treated and only second class treated wastewater is now discharged into coastal waters. The assessment of pressures on benthic habitats for the purposes of the MSFD, builds on the pressure analysis carried out as part of the Water Framework Directive, but covers a wider range of maritime activities and associated pressures in line with Annex III of the Directive. Table 5 provides an indication of the maritime activities which can potentially give rise to pressures and impacts on benthic habitats. The extent of benthic habitats affected by the various maritime activities was derived through superimposition of the activities or the pressures themselves (such as occurrence of non-indigenous species) on the benthic habitats. The significance or importance of such effects was assessed through a combination of a semi-quantitative assessment of the extent of affected benthic habitats, an evaluation of the reversibility or otherwise of the effect and expert judgement. The latter contributed significantly to the assessment of pressures, especially in view of the current data scenario with respect to benthic habitats. Table 6 reflects the outcome of the assessment of pressures on each MSFD habitat type. The assessment of pressures and impacts on benthic habitats was used to inform the overall assessment of status of the MSFD benthic habitat types. In particular, the assessment of pressures sheds light on the future prospects of the habitat type in line with the recommendations put forward through the Habitats Directive guidance document 193. Within this context, future trends of habitats is dependant on threats which will have a negative influence and on conservation measures and other provisions which will have a positive influence Assessment and reporting under Article 17 of the Habitats Directive: Explanatory Notes & Guidelines for the period Final Draft. April

57 Table 5: List of activities and associated pressures on benthic habitats under consideration for the purposes of the MSFD Sector Activity Annex III Pressure Fisheries Trawling Physical Loss Aquaculture N/A Physical Damage Physical Damage Contamination by hazardous substances Man-made structures Extraction of resources Energy Shipping (including Port Operations) Tourism and Recreation (including yachting) Waste Defence Land-based activities Land reclamation or Coastal Defence Submarine cables and pipelines Nutrient and Organic Enrichment Physical Loss Physical Damage Interference with Hydrological Processes Physical Loss Physical Damage Desalination/water abstraction Interference with Hydrological Processes Marine-based renewable energy generation Marine hydrocarbon extraction Coastal Defence Fuel terminals/bunkering Dredging Maritime Traffic Boating Yachting/Marinas Diving Sinking of vessels Disposal of solid waste Dumping of munition Industry Agriculture Municipal waste water discharge Physical Loss Physical Damage Interference with Hydrological Processes Physical Loss Physical Damage Contamination by hazardous substances Physical Loss Physical Damage Interference with Hydrological Processes Contamination by hazardous substances Physical Loss Physical Damage Interference with Hydrological Processes Contamination by hazardous substances Physical Damage (through anchoring) Contamination by hazardous substances Non-indigenous species Physical Damage (through anchoring) Physical Loss Physical Damage Interference with Hydrological Processes Contamination by hazardous substances Non-indigenous species Physical Damage Physical Damage Physical Loss Physical Damage Physical Damage Contamination by hazardous substances Interference with Hydrological Processes Contamination by hazardous substances Contamination by hazardous substances Nutrient and Organic Enrichment Contamination by hazardous substances Nutrient and Organic Enrichment 57

58 Table 6: Assessment of Pressures on MSFD benthic habitat types. +++ = effect is of high significance; ++ = effect is of moderate significance; + = effect is of low significance; N/A = Pressure is not applicable for the specific MSFD Habitat type; Reference to Potential pressure implies that current data scenario does not allow assessment of pressure on habitat type; Symbols in red indicate potential effect from planned activities currently under assessment. Habitats Pressures Sectors Physical Loss Fisheries Land/sea physical interactions; coastal defence (include structures related to harbours and marinas) Submarine cables and pipelines Dredging Marine-based renewable energy generation Marine hydrocarbon extraction Solid waste disposal Littoral Rock and Biogenic Reefs Littoral Sediment Shallow sublittoral rock and biogenic reefs Shallow sublittoral sediment (including Posidonia oceanica meadows) Shelf sublittoral rock and biogenic reefs Shelf sublittoral sediment Upper bathyal rock and biogenic reefs Upper Bathyal sediment N/A N/A N/A N/A N/A ++ N/A ++ N/A N/A + + N/A N/A N/A N/A N/A N/A N/A N/A N/A ++ N/A N/A N/A N/A N/A N/A N/A + Potential Potential N/A N/A N/A N/A N/A N/A Potential Potential N/A Potential N/A N/A N/A + N/A + N/A N/A Physical Damage Fisheries N/A N/A N/A + N/A ++ N/A ++ 58

59 Habitats Pressures Sectors Aquaculture Land/sea physical interactions; coastal defence (including structures related to harbours and marinas) Submarine cables and pipelines Dredging Littoral Rock and Biogenic Reefs Littoral Sediment Shallow sublittoral rock and biogenic reefs Shallow sublittoral sediment (including Posidonia oceanica meadows) Shelf sublittoral rock and biogenic reefs Shelf sublittoral sediment Upper bathyal rock and biogenic reefs Upper Bathyal sediment N/A N/A N/A N/A N/A N/A N/A + + N/A N/A N/A N/A + N/A N/A Potential + N/A N/A ++ N/A N/A N/A N/A Marine-based renewable energy N/A N/A N/A + Potential Potential N/A N/A generation Marine hydrocarbon extraction N/A N/A N/A N/A Potential Potential N/A Potential Shipping (anchoring and bunkering) N/A N/A N/A ++ Potential ++ N/A N/A Solid Waste disposal N/A N/A N/A + N/A + N/A N/A Tourism and recreation including boating, yachting, N/A N/A N/A N/A diving, sinking of vessels Defence: Dumping of unwanted munitions N/A N/A N/A N/A Potential Potential N/A N/A 59

60 Habitats Pressures Sectors Interference with hydrological processes Contaminatio n by hazardous substances Land/sea physical interactions; coastal defence Dredging Desalination/water abstraction Marine-based renewable energy generation Land-based activities: industrial discharges and emissions Aquaculture Dredging Littoral Rock and Biogenic Reefs Littoral Sediment Shallow sublittoral rock and biogenic reefs Shallow sublittoral sediment (including Posidonia oceanica meadows) Shelf sublittoral rock and biogenic reefs Shelf sublittoral sediment Upper bathyal rock and biogenic reefs Upper Bathyal sediment + ++ N/A + N/A N/A N/A N/A N/A N/A N/A + N/A N/A N/A N/A + N/A + + N/A N/A N/A N/A N/A N/A N/A + N/A + N/A N/A + N/A + + N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A + N/A N/A N/A N/A Marine hydrocarbon extraction N/A N/A N/A N/A Potential Potential N/A Potential Shipping (including port operations & N/A N/A N/A N/A bunkering) Defence: dumping of unwanted munitions N/A N/A N/A N/A N/A N/A N/A N/A Tourism and recreation including N/A N/A + + N/A N/A N/A N/A 60

61 Habitats Pressures Sectors Nutrient and organic enrichment Biological Disturbance Littoral Rock and Biogenic Reefs Littoral Sediment Shallow sublittoral rock and biogenic reefs Shallow sublittoral sediment (including Posidonia oceanica meadows) Shelf sublittoral rock and biogenic reefs Shelf sublittoral sediment Upper bathyal rock and biogenic reefs Upper Bathyal sediment boating, yachting, diving, sinking of vessels Coastal, riverine and atmospheric inputs from land industrial N/A N/A + + N/A N/A N/A N/A discharges and emissions Coastal, riverine and atmospheric inputs from land municipal N/A N/A + + N/A N/A N/A N/A waste water discharge Aquaculture N/A N/A + ++ N/A N/A N/A N/A Coastal, riverine and atmospheric inputs from land agriculture and forestry run-off and emissions ++ N/A ++ + N/A N/A N/A N/A Coastal, riverine and atmospheric inputs from land municipal ++ N/A ++ N/A N/A N/A N/A N/A waste water discharge Shipping (including + N/A + + N/A N/A N/A N/A port operations) Tourism and + N/A + + N/A N/A N/A N/A recreation including 61

62 Habitats Pressures Sectors boating, yachting, diving, sinking of vessels Littoral Rock and Biogenic Reefs Littoral Sediment Shallow sublittoral rock and biogenic reefs Shallow sublittoral sediment (including Posidonia oceanica meadows) Shelf sublittoral rock and biogenic reefs Shelf sublittoral sediment Upper bathyal rock and biogenic reefs Upper Bathyal sediment 62

63 1.5 Assessment of Status Assessment areas On the basis of the above description of benthic habitats, the current data availability and the distribution of marine activities, two major assessment areas were delineated to represent the different habitat types within each MSFD predominant habitat type category. These assessment areas incorporate the marine area off the North-eastern coast of the Maltese Islands up to and an area off the Southwestern coast of mainland Malta as indicated in Figure 14. Once new data becomes available, the assessment areas may be adjusted accordingly. The Northeastern assessment area is targeted at the assessment of littoral, shallow sublittoral and shelf sublittoral benthic habitats, while the Southwestern assessment area is targeted at the assessment of bathyal habitats. It should be noted that the extent of these assessment areas was delineated with the boundaries of the protected areas as designated through Government Notice 851 of 2010 and with the coastal water bodies as identified in Malta s Water Catchment Management Plan, as much as possible. As a result of the current data scenario, in which data is mainly available for the habitat types associated with the shallower depths, the assessment of status for the first reporting cycle was focused on the North-eastern assessment area. The Southwestern assessment area will be used in future reporting cycles specifically for bathyal habitat types, since to date, these have only been recorded from this area. It should also be noted that the Grand Harbour area designated as a Heavily Modified Water Body through the implementation of the Water Framework Directive for coastal water bodies, has been excluded from this assessment area. The reason is that the habitats within this area are highly modified as a result of port operations. Therefore such habitats will not be representative of the habitat types under consideration. Nevertheless, pressures associated with port operations were still taken into consideration in the assessment process and the achievement of good status within these areas will still be sought, also taking into consideration the existing commitments of the EU Water Framework Directive. 63

64 Figure 14: Proposed Assessment Areas for the assessment of benthic habitats The North-eastern assessment area incorporates most of the activities which are associated with pressures on the marine environment including: Aquaculture Bunkering areas Historical munition dumping ground Land-based discharges Marinas Mooring and anchoring areas; Pipelines Planned windfarms Power and telecommunication cables Spoil ground Swimming areas Trawling This assessment area also covers most of the past monitoring stations for contaminants and the most extensive Marine Protected Area designated within the framework of the Habitats Directive (Government Notice 851 of 2010). For most habitat types, assessment of status was restricted to these assessment areas unless it was deemed more adequate to assess particular habitats at other geographic scales. 64

65 1.5.2 Methodologies Assessment of status of benthic habitats is based on the criteria and indicators established by Commission Decision 477/2010/EU, also building on existing methodologies which are currently applied for the Habitats Directive and Water Framework Directive. The criteria and indicators for Descriptors 1, 4 and 6 reproduced hereunder are deemed to be relevant in terms of benthic habitats: Descriptor 1: Biological Diversity is maintained. The quality and occurrence of habitats and the distribution and abundance of species are in line with prevailing physiographic, geographic and climatic conditions Descriptor 4: All elements of marine food webs, to the extent that they are known, occur at normal abundance and diversity and levels capable of ensuring the long-term abundance of the species and the retention of their full reproductive capacity Descriptor 6: Sea-floor integrity is at a level that ensures that the structure and functions of the ecosystems are safeguarded and benthic ecosystems, in particular, are not adversely affected. The current status of data and information on benthic habitats in Malta precludes the possibility to apply all relevant criteria and indicators for MSFD Descriptors 1, 4 and 6. Further data would need to be collected to allow the application of all relevant criteria and indicators. 65

66 Table 7 lists the criteria and indicators which were used for determination of status for particular habitat types. However, it should be noted that assessment of status on the basis of these selected criteria was still not possible for all habitat types, also in view of data limitations. In such circumstances efforts have been made to determine status through expert judgement. 66

67 Table 7: Criteria and indicators on which assessment of status of benthic habitats for the first reporting cycle of the MSFD is based. Criteria Indicators Methodologies (Sources) Habitat Distribution (1.4) Distributional range (1.4.1) Habitat extent (1.5) Habitat area (1.5.1) Physical Damage, having regard to substrate characteristic (6.1) Habitat Condition (1.6) Condition of benthic community (6.2) Type, abundance, biomass and areal extent of biogenic substrate (6.1.1) Condition of the typical species and communities (1.6.1); Relative abundance and/or biomass as appropriate (1.6.2) Presence of particularly sensitive and/or tolerant species (6.2.1) Assessment and reporting under Article 17 of the Habitats Directive: Explanatory Notes & Guidelines for the period Final Draft. April CARLIT, PREI and AMBI index as applied for the WFD monitoring programme The application of habitat distribution and extent (criteria 1.4 and 1.5) criteria for determination of status builds on the requirements of the Habitats Directive in determining Conservation Status. According to Habitats Directive s Article 17 guidance document, the evaluation of status based on range should consider the size of the range in relation to the size of the favourable range and trends. Given the current status of available data, particularly the fact that most of the data constitutes snapshot data, the possibility to use trends to assess status through this methodology was ruled out. The calculation of Favourable Reference Range and Favourable Reference Areas, based on the guidance provided in Article 17 guidance document, was possible only for habitat types of which ecological requirements are relatively well known. Reference ranges and areas could not be determined for each habitat also in view of the dearth of information which is available with respect to substrate types and other physical aspects of the marine environment which would establish the conditions for the different habitat types. With respect to condition of benthic habitats (criteria 1.6 and 6.2), the methodologies used in determining status are based on those currently utilised for assessing ecological status of the Biological Quality Elements under consideration through the Water Framework Directive. This is due to the fact that the Habitats Directive does not specify how structure and functions can be evaluated. As per WFD methodologies, the ecological status is expressed as a ratio between the values of the biological elements observed by a given body of surface water and the value for these elements in reference conditions. However these methodologies were only applied for habitat types which are currently being monitored as part of the implementation of the Water Framework Directive. 67

68 The overall assessment of status on the basis of the above-mentioned criteria and indicators was supplemented by information on the extent and location of pressures in the marine environment (refer to section 1.4 of this document) and was subject to expert judgement throughout the whole process. With respect to the boundaries between Good status and Not Good, the thresholds for such boundaries were determined on a case by case basis through expert advice. However a general indication of the basis of such thresholds is provided in Table 8. Table 8: General indication for determination of thresholds between Good and Not good status. Moderate Criteria Indicators Good Status Poor Status Status The range and The range and The range and extent of the extent of the Habitat Distributional extent of the habitat type, habitat type, Distribution (1.4) range (1.4.1) habitat type, when compared when compared when compared to favourable to favourable to favourable reference values reference values Habitat extent Habitat area reference values and/or based on and/or based on (1.5) (1.5.1) and/or based on expert expert expert judgement, have judgement, have judgement, are been altered or been significantly not significantly are likely to be affected by Physical Damage, Type, abundance, altered by affected by anthropogenic having regard to biomass and anthropogenic anthropogenic factors in a substrate areal extent of activities. Future factors. Future manner which characteristic biogenic prospects secure prospects for puts the long (6.1) substrate (6.1.1) the long-term maintenance of term viability of viability of the the range and the habitat type habitat type. extent are good. at risk. Habitat Condition (1.6) Condition of benthic community (6.2) Condition of the typical species and communities (1.6.1); Relative abundance and/or biomass as appropriate (1.6.2) Presence of particularly sensitive and/or tolerant species (6.2.1) The structural aspects 194 of the benthic habitat or the composition and abundance of species associated with the habitat type corresponds to undisturbed conditions or is only slightly altered relative to undisturbed conditions 195 The structural aspects of the benthic habitat or the composition and abundance of species associated with the habitat type are indicative of moderate changes relative to undisturbed conditions 196. The structural aspects of the benthic habitat or the composition and abundance of species associated with the habitat type are indicative of significant changes relative to undisturbed conditions 194 The structural aspects for marine habitats listed in the EU Habitats Directive (1110, 1120 and 1170) are defined in Assessment and reporting under Article 17 of the Habitats Directive: Explanatory Notes & Guidelines for the period Final Draft. April

69 1.5.3 Assessment of Status The following outlines the assessment of status for the MSFD predominant habitat types, and where necessary, for specific habitat types (Table 10). Littoral Rock and Biogenic Reef: Communities of mediolittoral macroalgae characterised by Cystoseira species were used as the indicator species of Littoral Rock and Biogenic Reefs. The status of such communities was assessed on the basis of the range and extent covered by Cystoseira species (in terms of length of coastline) within the north-eastern assessment area. In accordance with the Habitats Directive Article 17 guidance, the natural range constitutes the spatial limits across the north-eastern assessment area within which this habitat type occurs. The range should exclude major discontinuities due to natural factors, which for Cystoseira on littoral rock would be mainly represented by sandy or shingle beaches. However due to the limited extent of sandy or shingle beaches on the Maltese Islands (total length of c.3km), they were not considered to be major discontinuities in the range of the habitat type in question. Within this context, the Favourable Reference Range of Cystoseira communities was considered to be the extent of rocky coast within the north-eastern assessment area. The Favourable Reference area on the other hand was considered to be the extent of rocky shoreline within the north-eastern assessment excluding sandy or shingle beaches. However this reference area is not taking into consideration the presence of particular geomorphological features along the coastline, which would not be colonised by Cystoseira communities. Therefore in reality, the Favourable Reference Area of this type of community could be much less than that determined for this reporting cycle. Such issues should be tackled in future reporting cycles. The current range of Cystoseira communities is considered to occupy the whole range of littoral rock (excluding harbours) along the north-eastern coast, while the extent of coastline occupied by Cystoseira communities constitutes c. 66% of the rocky coastline excluding sandy or shingle beaches. This percentage however does not take into consideration the influence of geomorphological factors on the distribution of Cystoseira communities, therefore the absence of Cystoseira from the remaining coastline could be due to both natural and anthropogenic factors. Based on expert judgement and the extent of coastline for which absence of Cystoseira can be attributed with certainty to anthropogenic disturbance (approximately 3% of the current extent of Cystoseira communities), the status of this community is considered to be overall good in terms of habitat distribution and extent. 195 Based on the definition of high and good status as defined for the various biological quality elements as per Water Framework Directive. 196 Based on the definition of moderate status for the various biological quality elements of the Water Framework Directive 69

70 Assessment of the habitat condition was extrapolated from the outcome of the baseline monitoring, which at the time of writing this document, is being undertaken for the purposes of the EU Water Framework Directive 197. Monitoring and assessment of status of macroalgae, as one of the Biological Quality Elements under consideration by the WFD, was based on the CARLIT methodology as defined by Ballesteros et al. (2007) 198. Five out of eleven stations analysed by application of the CARLIT index through the WFD baseline monitoring are located in the north-eastern assessment area. Calculation of the ratio between the CARLIT index and reference values (or maximum values of the CARLIT index) calculated for Maltese coast typologies, resulted in three of these sampled sites qualifying as High Ecological Status and two as Good ecological status (Figure 15). This result corroborates with the findings of the 2008 survey, which survey applied the CARLIT methodology to the whole extent of the Maltese coast. According to this survey, most of the communities in the northeastern assessment area resulted in high good status, with a good status being attributed to the water body along the coastline which until recently was subject to effluent of untreated wastewater. The overall status of this habitat type is considered to be good. 197 CIBM & Ambiente SC Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys Water Lot 3 Surveys of Coastal Water August ERDF156 - Developing national environmental monitoring infrastructure and capacity 198 Ballesteros, E.; Torras, X; Pinedo, S.; Garcia, M.; Mangialajo, L. & detorres, M A new methodology based on littoral community cartography dominated by macroalgae for the implementation of the European Water Framework Directive. Marine Pollution Bulletin 55:

71 Figure 15: Stations assessed through the CARLIT methodology as part of the WFD monitoring regime Littoral sediment This predominant habitat type is represented by sandy and shingle beaches along the Maltese coastline. Given the localised nature of such beaches, assessment of status is based on a selection of beaches made in accordance with the following criteria: Beaches of which extent does not vary seasonally and are thus considered to be permanent beaches; Beaches of relatively significant length which can potentially support beach ecosystems; Natural beaches, thus excluding any beaches which have been subject to beach replenishment projects. The beaches which will be used in assessing status are the following (Figure 16): Ir-Ramla and il-bajja ta San Blas, on Gozo Il-Qala ta Santa Marija, on Comino Il-Bajja tal-ġnejna, Ir-Ramla tal-mixquqa, Ir-Ramla ta Għajn Tuffieħa and the shingle beach at Fomm ir-riħ on the southwestern coast of mainland Malta; Ir-Ramla tat-torri, Ir-Ramla tal-qortin, Ir-Ramla tal-armier, Little Armier and il-bajja tal-mellieħa on the north-eastern coast of mainland Malta. 71

72 Figure 16: Selected sandy beaches and shingle beach for MSFD assessment purposes In accordance with Habitats Directive Article 17 guidance document, the distributional range of such localised habitat types would be equivalent to their extent. Within this context, these two parameters were calculated as length of shoreline occupied by each beach, measured on the basis of 2008 aerial photographs. These beaches cover a total length of 2419m (Table 9: Table 9: Estimates of lengths of selected beaches based on the 2008 aerial photographs Beach Length (m) calculated on the basis of the 2008 aerial photographs Ramla (Gozo) San Blas (Gozo) 91.4 Santa Marija (Comino) Ramla tal-mixquqa Għajn Tuffieħa 275 Ġnejna Bajja tal-mellieħa Ramla tal-qortin 97.8 Armier Little Armier 73.4 Ramla tat-torri Fomm ir-riħ

73 Trends in the extent of beaches are based on expert judgement. In general, experts deem that the extent of beaches has decreased 199 as a result of development on the coast and on land, affecting coastal erosion processes and sediment supply respectively. These effects take place gradually over a long period of time and effects of past developments are still being observed to date and are expected to continue in the future. Given current environmental assessment processes, the expected decrease in range/extent is more related to the long term effects of past developments rather than future development, which effects cannot be addressed at this stage. For this reason, sandy and shingle beaches are currently considered to be of moderate status in terms of distribution/extent. Assessment of habitat condition is based on records of species, of which presence is indicative of a functioning beach ecosystem. Such species include Ophelia bicornis, Tylos europaeus on sandy beaches, Tylos ponticus on gravel, pebble and cobble beaches and talitrid amphipods. Expert judgement based on the presence/absence of such indicator species indicates that four out of the selected beaches are considered to be in good status; seven of moderate status and one of poor status. Overall status in terms of habitat condition is also deemed to be moderate. Shallow sublittoral rock and biogenic reef: Assessment of status for shallow sublittoral rock focuses on photophilic algal communities associated with bedrock within the 0-5m depth zone. This assessment excludes specific geomorphological features forming part of the shallow sublittoral rock category, namely boulder shores, caves and overhangs, all of which generally support sciaphilic algae as enclaves of deeper water communities. This is due to the fact that data pertaining to the distribution of these geomorphological features is limited, thus precluding the possibility to use such communities for assessment purposes. Posidonia oceanica meadows growing on outcropping bedrock within the 6-45m depth zone are also being excluded from this assessment of status, since such meadows are assessed separately as a special habitat type listed in Annex I of the Habitats Directive. The currently available data pertaining to photophilic algae within the 0-5m depth zone constitutes patchy snapshot data which presented difficulties in applying current methodologies for assessment of status. Assessment was thus strongly based on extrapolation of current data and expert judgement. Data was extrapolated on the basis of the location of the 5m bathymetric contour, the presence of shallow sublittoral sediment (hence absence of sublittoral rock), indication of the presence of bedrock by Admiralty charts and habitat condition assessed for Littoral Rock and Biogenic Reefs (Figure 17). 199 This is a general statement and it should be noted that such decrease is not associated with all the selected sandy beaches, some of which might have actually increased in extent specifically Ramla (D.T. Stevens, personal communication). 73

74 The use of data on littoral rock and biogenic reefs for extrapolation purposes is justified in view of the similarities between the two habitat categories. Algal communities within the 0-5m depth zone are also dominated by Cystoseira, albeit belonging to different species than those characterising the littoral zone, and are generally considered to be a continuation of the communities occupying the littoral zone. Cystoseira species on both littoral and sublittoral rock are considered to be indicators of good environmental quality, which in the 0-5m depth zone are replaced by other algal species such as Pterocladia capillacea and Ulva laetevirens in disturbed areas. Based on actual and extrapolated data this habitat type covers circa 5km 2 within the 0-5m depth zone (3.078km 2 from available data and 1.921km 2 from extrapolated data). The only extent of this bedrock which is known to be altered due to anthropogenic activities (also extrapolated from data on Littoral Rock) constitutes less than 10% of the calculated extent. Status in terms of habitat condition is based on the presence of Cystoseira species in the 0-5m depth zone as extrapolated from the data on Littoral Rock and biogenic reefs, also coupled to expert judgement. Overall, the status of shallow sublittoral rock based on the extrapolated data on photophilic algae and expert judgement, is considered to be good. Figure 17: Actual and extrapolated data on which assessment of shallow sublittoral rock was based. 74

75 Shallow sublittoral sediment: Assessment of status for shallow sublittoral sediment excludes Posidonia oceanica meadows settled on sand or matte, since this habitat type is being assessed separately as a special habitat type listed in Annex I of the Habitats Directive. Shallow sublittoral sediment is characterised by different benthic communities, the distribution of which depends on the varying sediment characteristics. The current data scenario does not allow distinction amongst these communities, implying that assessment of status for this predominant habitat type would reflect status of a composite of benthic communities associated with different grades of sediment ranging from mud to gravel. This composite also includes seagrass meadows dominated by Cymodocea nodosa. This habitat type is considered to be very dynamic in nature and determination of its distributional range and extent based on the currently available snapshot data will not necessarily reflect its status. Indeed, the information available for shallow sublittoral sediment in general is based on localised and snapshot data. As for Shallow sublittoral rock and biogenic reefs the current data was extrapolated on the basis of the presence of P. oceanica meadows and bedrock, and the location of the 50m bathymetric contour. Determination of the range and extent of shallow sublittoral sediment was thus based on actual (12.3km 2 ) and extrapolated data (38.1km 2 ) (Figure 18). Based on expert judgement, and in the knowledge of the fact that this habitat type is only affected by localised pressures (such as aquaculture and recreational activities within the innermost parts of bays), the extent of this habitat type is deemed to be in line with the natural physiographic, and is thus considered to be of good status. 75

76 Figure 18: Actual and extrapolated data on which assessment of shallow sublittoral sediment was based. The determination of status for shallow sublittoral sediment in terms of habitat condition (criterion 6.2) was based on the data generated on benthic invertebrates as part of the current baseline monitoring of the EU Water Framework Directive 200. Through this monitoring, shallow sediments (mud, sand and gravel) were sampled for the analysis of benthic invertebrates with a view to apply the AMBI index for softbottom macrofauna in accordance with Borja et al. (2000) 201. This index is designed to establish the ecological quality of coastal waters based on the response of softbottom communities to natural and anthropogenic induced changes in water quality. The degree of impact is reflected by changes in the qualitative and quantitative community composition. The interim results of such monitoring indicate that all sampled stations can be assigned to the slightly disturbed category with the exception of one sampling station along the coast of Gozo which can be assigned to the category undisturbed and is used as a reference station. Only this station was assigned a high ecological status, while the rest of the stations are deemed to be in a good ecological status. Four sampling stations which are currently being monitored are located in the Northeastern assessment area (Figure 19). 200 CIBM & Ambiente SC Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys Water Lot 3 Surveys of Coastal Water August ERDF156 - Developing national environmental monitoring infrastructure and capacity 201 Borja, A.; Franco, J. & Pérez, V A Marine Biotic Index to Establish the Ecological Quality of Soft-bottom benthos within European Estuarine and Coastal Environments. Marine Pollution Bulletin 40 (12):

77 The status of this habitat type is thus deemed to be overall good. Figure 19: Stations assessed through the AMBI index as part of the WFD monitoring regime Posidonia oceanica meadows: The status of P. oceanica meadows has been assessed on different occasions in the past twelve years. In 1995, a preliminary assessment based on the spatial and bathymetric distribution, general health and plant morphological characteristics, indicated that dense and healthy meadows cover large areas in inshore waters although some regression was reported in areas subject to anthropogenic pressures 202. The 2007 Habitats Directive reporting assigns a favourable status to P. oceanica (code 1120) 203, which status was mainly based on expert judgement of the benthic surveys carried out mostly in In 2009, a study which focused on assessment of status of P. oceanica at four locations also indicated that the overall state of health of Posidonia oceanica was good Borg, J.A. & Schembri P.J. (1995): The state of Posidonia oceanica (L.) Delile meadows in the Maltese Islands (Central Mediterranean); Rapp Comm Int Mer Medit 34 p Borg, J.A.; Rowden, A.A.; Attrill, M.J.; Schembri, P.J. and Jones, M.B Occurrence and distribution of different bed types of seagrass Posidonia oceanica around the Maltese Islands; Mediterranean Marine Science 10(2);

78 Experts confirm that with the exception of localised areas in which Posidonia oceanica meadows are known to have regressed as a result of anthropogenic disturbance (mainly harbour areas), the current range and extent of P. oceanica are in line with the physiographic and climatic conditions of the seabed. Within this context, experts have confirmed that even when P. oceanica colonises areas outside the current range and extent, such colonisation would not be viable, presumably since natural conditions within such areas do not represent the required conditions by the seagrass (J.A. Borg & P.J. Schembri, personal communication). Posidonia oceanica constitutes a Biological Quality Element which needs to be assessed within the framework of the Water Framework Directive. The baseline monitoring which is currently in progress for the purposes of the Water Framework Directive 205 is assessing the status of Posidonia oceanica meadows through the application of the Rapid Easy Index (or PREI index) which was the method selected through the intercalibration exercise for the Mediterranean region. This index is based on the following attributes: Shoot density Shoot surface Ratio between epiphytic biomass and leaf biomass; Depth of the lower limit Type of this limit (regressive, progressive or stable). Reference conditions in this case referred to a theoretical optimal site determined on the basis of the second and third highest values for shoot density and shoot surface area. The surveys were carried out in May and June 2012 in 10 sampling stations, seven of which are interspersed within the north-eastern assessment area. Based on the data collected and the methodologies outlined above the ecological status of P. oceanica qualified as being of high ecological status for three sites within the north-eastern assessment areas and of good ecological status for the remaining two sites (Figure 20). These two sites are located off Sliema coast and between Valletta and Marsaxlokk and are probably influenced by anthropogenic activities 206. This indicates that Posidonia meadows within this area can be considered healthy and that habitat condition as per criteria is of good status. It should be noted that the attributes used for assessment of status, are very similar to the structural aspects defined for Posidonia oceanica by the Explanatory Notes and Guidelines for assessment and reporting under Article 17 of the Habitats Directive 207. Therefore assessment of the habitat condition based on the PREI index would also reflect the status of the structure and functions as defined by the Habitats Directive. 205 CIBM & Ambiente SC Development of Environmental Monitoring Strategy and Environmental Monitoring Baseline Surveys Water Lot 3 Surveys of Coastal Water August ERDF156 - Developing national environmental monitoring infrastructure and capacity 206 ditto 207 Assessment and reporting under Article 17 of the Habitats Directive: Explanatory Notes & Guidelines for the period Final Draft. April

79 Figure 20: Stations assessed through the PREI index as part of the WFD monitoring regime Shelf sublittoral rock and biogenic reefs The data available on shelf sublittoral rock and biogenic reefs is too limited to allow any type of assessment of status. In general, it is presumed that waters at depths greater than 50m are mainly characterised by sediment rather than rock, with the latter only occupying localised areas within this depth zone (J.A. Borg & P.J. Schembri, personal communication). However the location of such areas is not known. On the other hand, this type of habitat is probably not subject to significant pressures from anthropogenic activities, hence even if the status cannot be determined at this stage, such habitat type is expected to be in good status. Shelf sublittoral sediment: Assessment of shelf sublittoral sediment focuses on coarse sediments with rhodoliths and maerl beds, the distinction between which depends on the predominance of rhodoliths in the sediment. In maerl beds, rhodoliths constitute a dominant component of the sediment, however there is no quantitative estimate of 79

80 rhodoliths which would distinguish between sediment with rhodoliths and maerl beds. Localised data for this habitat type verifies the presence of a maerl bed off the North-eastern coast of mainland Malta, covering an extent of the seabed of about 30km 2 (this value is calculated from the extent of maerl bed as plotted in MEPA s data repository published data indicates that the extent of this maerl bed is circa 20km 2 ). Another 8.5km 2 of seabed off the Southeastern coast of Malta is characterised by both sediment with rhodoliths and maerl. Based on this localised data, coarse sediments with rhodoliths and maerl beds cover an area of about 40km 2 within the North-eastern assessment area. However, a recent survey of the seabed by Micallef et al. (2013) 208 indicates a much larger expanse of the seabed characterised by maerl, sand and gravel. Assuming that this area constitutes an expanse of the seabed supporting various grades of coarse sediments with rhodoliths ranging from sparse rhodoliths to maerl beds, this habitat type would cover at least 77km 2 of the north-eastern assessment area (Figure 21). It should be acknowledged however that this value may also include coarse sediments without rhodoliths. The distribution and extent of this habitat type within the north-eastern assessment area needs further analysis, particularly to verify the presence or otherwise of such habitat to the East of mainland Malta. Assessment of status is completely based on expert judgement since the currently available data does not lend itself to the application of standard methodologies for determination of status on the basis of distributional range, extent and condition. On the other hand, it should be noted that the experts involved in this assessment have been studying the 30km 2 maerl bed off the north-eastern coast of Malta, located within the area of Maerl, sand and gravel indicated by Micallef et al (2013) 209, since Within this context, assessment of status focuses on the major maerl bed off the north-eastern coast of the Maltese Islands, which is deemed to be in good status in terms of range and extent. Such status can be extrapolated to cover the whole extent of Maerl, sand and gravel as indicated by Micallef et al. (2013). Habitat condition has not been assessed at this stage. However given the low pressures to which the major maerl bed off the north-eastern coast of the island is subject to, status in terms of habitat condition is deemed to be good (in terms of the extent of the seabed significantly affected by human activities) 208 Micallef, A.; Foglini, F.; LeBas, T.; Angeletti, L.; Maselli, V.; Pasuto, A. & Taviani, M The submerged paleolandscape of the Maltese Islands: Morphology, evolution and relation to Quaternary environmental change. Marine Geology. 335: ditto 80

81 Figure 21: Distribution of sediment with rhodoliths and maerl beds based on localised data superimposed on the extent of Maerl, Sand and Gravel as extracted from Micallef et al. (2013) 210 Upper Bathyal Rock and Biogenic Reefs: Given the current data limitations with respect to upper bathyal rock and biogenic reefs, it was not possible to assess status of this predominant habitat type for this MSFD reporting cycle. Upper Bathyal Sediment: Given the current data limitations with respect to upper bathyal sediments, it was not possible to assess status of this predominant habitat type for this MSFD reporting cycle. 210 Micallef, A.; Foglini, F.; LeBas, T.; Angeletti, L.; Maselli, V.; Pasuto, A. & Taviani, M The submerged paleolandscape of the Maltese Islands: Morphology, evolution and relation to Quaternary environmental change. Marine Geology. 335: