IMO HARMFUL AQUATIC ORGANISMS IN BALLAST WATER. Description of the proposed model groups defined under Tier 1. Submitted by Norway

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1 INTERNATIONAL MARITIME ORGANIZATION E IMO MARINE ENVIRONMENT PROTECTION COMMITTEE 47th session Agenda item 2 MEPC 47/INF December 2001 ENGLISH ONLY HARMFUL AQUATIC ORGANISMS IN BALLAST WATER Description of the proposed model groups defined under Tier 1 Submitted by Norway SUMMARY Executive summary: This document presents a detailed description of representative species from the proposed model groups, and how they can be used in a standardised test for type approval of ballast water treatment technologies. Action to be taken: See paragraph 4 Related documents: MEPC 47/2, MEPC 47/2/8, MEPC 47/INF.5, MEPC 46/3/8 Introduction 1 MEPC 46 developed two possible options in the development of a Ballast Water Treatment Standard (MEPC 47/2, paragraph 4.6). One option is to use representative species from five taxonomic groups. Following that preliminary conclusion Norway has submitted information on that matter to the Ballast Water Standard Correspondence Group (MEPC 47/INF.5). In order to progress on the matter at MEPC 47, this document presents additional information on representative species of five possible model groups. 2 The criteria for selecting the five model groups are primarily functional, as they will cover different life stages of representative organisms. This manner of selecting model groups will cover a wider range of organisms and be adaptable to the variations within different treatment systems. These model groups will cover different size classes, different habitats, life-stages and a wide range of taxonomic groups. 3 In MEPC 47/2/8 Norway proposes the five model groups which can be used in a Ballast Water Treatment Standard (see table 1). A more detailed description of the five model groups is given in the annex to this document. For reasons of economy, this document is printed in a limited number. Delegates are kindly asked to bring their copies to meetings and not to request additional copies.

2 - 2 - Table 1 Selection of model groups for the Ballast Water Treatment Performance Standard. Model group (Functional group) Bacteria / Microalgae Pelagic invertebrates Benthic invertebrates Cysts/Dormant life-stage Macroorganisms Suggested representative species for testing/certification purposes Natural bacterial/algal populations Artemia salina e.g. Corophium sp. (Crustacea) Abra alba (Mollusca), Capitella capitata (Annelida) Bacillus sp. Spores Action requested of the Committee 4 The Committee is invited to note the information provided in this document and comment as it deems appropriate. ***

3 Description of the proposed model groups defined under Tier one Model group 1: Bacteria / Microalgae Involves living, natural or cultured populations of pelagic micro-organisms, relevant for natural seawater. The selected organisms should be distributed in the size range of 0 µm to <100 µm. The preferred population is a natural population, containing >100 % of the normal population density. Treatment effects may be measured in the form of respiration (O 2 -consumption), living cell count, or growth following a treatment. Cell/organism density may not be measured using chemical markers (chlorophyll fluorescence/atp concentration) as these may be independent of survival of individual organisms. Examples of suitable organisms are: Heterotrophic bacteria - Typically 5x10 6 cells/ml in euphotic zone and 10 3 cells/ml in deep ocean. Phytoplankton Cyanobacteria, previously known as the Blue Green Algae. - A common marine example is Oscillatoria sp., found in tropical waters and may cause them to appear orange-brown. - Picoplanktonic Synechococcus sp. May be cells/ml - important in primary production. Diatoms Dinoflagellates - Two forms: Desmophyceae Dinophyceae - Some species produce toxic blooms Coccolithophorids - Emiliania huxleyi most widespread. Prymnesiophytes eg Phaeocystis Silicoflagellates Model group 2: Pelagic invertebrates Involves all groups of organisms normally associated as pelagic invertebrates. Those which live in the water column. They include plankton (carried by the currents), nekton ( able to control their position by swimming), neuston (at or on sea surface), pleuston ( in air/water interface).

4 Page 2 Pelagic invertebrates could be divided into functional groups like zooplankton and nekton. Zooplankton: animals with locomotive powers that cannot prevent passive movement by currents. These include: - Cnidarians (medusae (jellyfish), siphonophores (colony of specialised individuals eg Portuguese Man o War)), - Ctenophora (transparent animals with no nematocysts. E.g. 'sea=gooseberry, Pleurobranchia.Chaetognatha or arrow worms), - Annelida - Mollusca - Urochordata - Arthropoda - class crustacea - Copepods - Euphausiids - Amphipods - Ostracods - Cladocera - Mysids - Decapods Nekton Nekton are pelagic animals capable of swimming against a current. They are predominantly fish - vary in size, trophic level and depth adaptation. The category includes cephalopods (squid) and crustaceans (crabs, shrimp). This model group does not include cysts, eggs, or other dormant life-stages of these invertebrates. Most robust life-stage of the organism is preferred for testing, and may include larval, juvenile or adult life stage. Examples of suitable organisms are i.e Artemia salina. Artemia salina is initially considered a very suitable model group organism as the robustness of this species is well documented. Model group 3: Benthic invertebrates. Involves testing of invertebrates normally associated with benthic communities. > 70% of benthic species have reproductive stages in the plankton. Typical phyla of such organisms include: Phylum Porifera (Sponges) Phylum Cnidaria (or Coelenterata) Phylum Ctenophora (Combjellies) Phylum Platyhelminthes (Flatworms Phylum Nemertea (Ribbon worms) Phylum Nematoda (Nematodes or roundworms Phylum Annelida (Segmented worms) Phylum Sipuncula (Peanut worms) Phylum Pogonophora (Beard worms) Phylum Bryozoa ('Moss animals') Phylum Phoronida

5 Page 3 Phylum Brachiopoda (Lamp shells Phylum Mollusca Phylum Arthropoda Phylum Echinodermata Suitable species selected for testing purposes could be robust test organisms as i.e. Corophium sp. (Crustacea) Abra alba (Mollusca) and Capitella capitata (Annelida). Most benthic hazard species have a pelagic lifestage, and this lifestage is most likely the one responsible for transfer with ballast water. It could be preferred to use representative hazard organisms as model group species (pelagic life-stages) provided the use of these in treatment testing does not represent a risk of spreading the species to non-domestic areas. Pelagic lifestages should be considered within the pelagic model group, not benthic model group. Model group 4: Cysts, spores, and dormant life stages. This group is considered the most crucial, yet most difficult model group. Cysts, eggs, spores, and other dormant life stages are protected, living life stages that are encapsulated from the surrounding waters. Are extremely relevant for the migration of hazard species with ballast water. Includes fish eggs (non-hatched), invertebrate hibernating life-stages, phytoplankton dormant stages etc. May be measured as hatchability or survival following a treatment, or as direct viability of each egg/cyst. Some species of dinoflagellates produce preservable organic walled resting cysts (hypnozygote dinocyst) after sexual reproduction that sinks to the sea floor after being produced. Some larvae are capable to stop their development into juvenile and adult if the environmental conditions are not optimal. Bacterial spores are considered to be the most resilient life-stage for such micro-organisms. Commercially available, non-pathogenic strains of Bacillus sp. spores are considered to be very suitable model group organisms. Model group 5: Macroorganisms. Involves fish, plants or macroalgae normally associated with natural seawaters. The selected group of organisms should be relevant for the treatment method (do not use plants to evaluate a herbicide chemical treatment etc.). Suitable organisms include fish (adults), kelp, seaweed or plants. Does not include juvenile fish, planktonic or single cellular life-stages (cysts, macroalgal spores, and plant seeds). Macro-Algae Chlorophyta (green algae) Rhodophyta (red algae) Phaeophyta (brown algae) Fish: AGNATHA CHONDRICHTHYES OSTEICHTHYES