PEKA PEKA FIVE YEAR RESTORATION PLAN

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1 PEKA PEKA FIVE YEAR RESTORATION PLAN BACKGROUND Pekapeka is located on the Kapiti Coast between Te Horo in the north and Waikanae to the south. The dune area is a Kapiti Coast District Council (KCDC) reserve. Local residents are currently forming a care group. There is one formal accessway and a number of informal ones. The dunes have significant weed issues, but spinifex well established in some places. The Restoration Plan is to cover the area from the private property boundaries including a wetland on the backdunes through to the foredunes. Some flax plantings have been established in a stormwater swale within the backdunes. The local Coast Care group has been granted $19,000 from Greater Wellington (GW) over the next five years to undertake restoration work. KCDC are likely to provide additional weed control which may include funding a contractor. SCOPE OF THIS PLAN The main area defined by GW for this Restoration Plan is the dune system seaward of the Marram Way subdivision at Peka Peka. (Fig. 1). The area is approximately 1ha in extent (Grid Reference: N E ). This report provides a brief description of the coast along Peka Peka including vegetation cover and local geomorphology. Selected earlier work that is relevant to vegetation restoration and management is also considered. The major component of the plan is detailed site-specific descriptions and management options for separate areas that have been defined within the study site at Peka Peka. A detailed timeline is also provided for undertaking restoration activities within each defined area for up to five years.

2 Marram Way Figure 1: The dune system along the coast at the Marram Way subdivision at Peka Peka, Kapiti Coast, to be covered by this restoration plan. [Need to replace this with GW GIS area from project brief] SITE INSPECTIONS The dune system at Peka Peka was inspected on 20 th April 2009 with GW staff, KCDC staff and representatives of the local care group. BRIEF SITE DESCRIPTION The dune at Peka Peka is a relatively wide, approximately 60m including foredune, dune slack and a small wetland formed in a swale. There is one central accessway used by the local community.

3 Botanical The foredune is dominated by spinifex but some marram grass is present on the seaward face. The backdune site comprises a dense cover of mainly exotic species including marram grass, and Australian coastal plant Correa alba, boneseed, lupin, and iceplant (Figure 2). Figure 2: View looking south along the backdune area A small wetland area has been established in a swale in the backdune designed to take stormwater when the subdivision was established. Harakeke planted four to five years ago appears vigorous and the once ephemeral ponding area is now dominated by native wetland rush and juncus spp. (See figure 3) Figure 3: Harakeke planted four to five years ago in ephemeral wetland area.

4 Wildlands (2008) provide a brief description of the dunes at Peka Peka describing the foredunes with spinifex and marram grass and shrub backdunes including presence of exotic shrub species. Geomorphological The area of Peka Peka dunes covered within this Restoration Plan is part of a the continuous coastal dune system along the Kapit / Otaki Coast. As such the foredune can be expected to be subject to storm wave attack on a regular basis. Maintainence of a vigorous cover of native sand binding grasses on the foredune is important to ensure the restoration efforts further landward are protected. SITE-SPECIFIC MANAGEMENT OPTIONS The section of dune at Peka Peka has been divided in three areas (Figure. 4). Management issues and a description of the dune morphology and vegetation cover are provided for each area along with recommended site-specific management options. Figure 4: The three areas identified of the Peka Peka dune system where site-specific descriptions and recommended management options are outlined.

5 AREA A Foredune zone (Figure 5) Description Moderately sloping foredune with a dense cover of mainly spinifex ranging from 5-8m wide and 200m along the beach. One centrally located dense patch of marram grass. Small active blowouts in the vicinity of the single formal pedestrian accessway leading from the subdivision. Figure 5: View south over the Peka Peka foredune Management options Re-align the end of the accessway on the foredune zone to reduce erosion and loss of windblown sand inland from prevailing onshore winds. Place the first 5-8 m at an angle to the coastline and 'dogleg' back to the existing track over the semi-stabilised backdune. Remove the dense marram grass over a two to three year period, slowly replacing it with spinifex. Spray the marram grass with Galant herbicide and replant with pingao within the marram area. Herbicide control of resprouting marram grass can be continued as Gallant won't affect the pingao. Fertilise edges of existing spinifex of bare sand areas where marram grass has been successfully controlled and other bare sand areas adjacent to realigned accessway.

6 AREA B Backdune zone (Figure 2 and 3 and Includes AREA C) Description The zone for this Plan spans 200m along the coast seaward of the Marram Way subdivision.the semi-stable undulating dune is less than 1ha extending approximately 40m wide from the landward edge of the foredune to the property boundaries. The backdunes in this area are dominated by exotics, some of which are aggressive and need immediate control A dense mixed cover of mostly exotic species with scattered patches of native species, particularly wiwi extends from the landward edge of the sand binding foredune zone to the property boundaries. Marram grass dominates the seaward part of the backdunes with an increasing number of other exotic grass species and exotics shrubs including boxthorn and pampas. A dense colony of the Australian coastal plant Corea alba inhabits the crest of the dune at the southern end and is actively spreading. Management options The priority is to locate and control the potentially most aggressive exotic species including the Corea alba and boneseed. A combination of handcutting and herbicide application will be required. As resources permit remove scattered other problem exotic species (e.g. boxthorn and pampas) as resources permit to reduce spread both vegetatively and via seed production. Use standard techniques for removal of vegetation such as hand cutting of stems for larger plants and swabbing stumps with herbicide, spraying crowns of smaller plants, or hand pulling of seedlings where practical. A large base of knowledge exists on control of these species. Community members can access this via specialist council officers and the 'Weedbusters' network. (

7 AREA C Southern part of backdune area Management options Focus restoration efforts on the backdune in one area initially such as the most southern part of the backdune, before moving northward (as resources allow). Establish small groups of key native backdune species where exotics shrubs have been removed or where gaps have been created within marram grass by weedeater and spraying of Gallant. Enhance existing native vegetation by clearing adjacent small areas of exotics and planting more natives. Groups to comprise 3-10 plants each depending on the size of the gap and resources available to supply plants and carry out maintenance, principally weed control. Key backdune species include taupata, wharariki, ngaio, wiwi, ti kouka, harakeke. Use taller growing species in hollows or swales to reduce concerns with sea views. In the backdune areas there are already some existing natives and as such not all the areas need to be planted. Using a planting regimes of 1-2 m spacing the area will require less than 5000 plants even if groups have dense plant spacing of cm between plants. Some existing natives already so not all area needs to be planted. A key part of the five year restoration strategy is to monitor the success of plant performance and implement timely maintenance, particularly weed control.

8 SITE-SPECIFIC FIVE-YEAR RESTORATION PLAN In developing the recommendations below (Table 1) we have taken into account the following site specific factors: Recommended priorities for actions and resources are only provided in detail for Years 1 and 2, and based on a budget of approximately $10,000 per year to cover the cost of plants, any contractor time and other materials. Only general guidelines are given for Years 3-5 as this is dependent on actions undertaken and performance of restoration over the first two years. Plant numbers are based on a maximum of 500 plants to be planted comfortably within a single morning session by a community group with persons attending. Table 1: Recommended priorities for actions and resources required for restoration of Marram Way dunes, Peka Peka, Kapiti Coast. Area(s) Year(s) Actions Resources required A 1 & 2 Re-align accessway at the foredune toe at an angle to the prevailing onshore wind to reduce sand movement. A 1 & 2 Spray marram grass progressively and replace with pingao; encourage spread of spinifex with limited broadcasting of fast release fertiliser along edges of colonies. B 1 Initiate removal of the most vigorous weeds including Corea alba, boneseed, pampas. C 1 Plant up gaps left after removal of woody weeds using native backdune plants such as wiwi on elevated sites and taupata and harakeke in swales. Community input, labour, basic fencing materials 'Gallant', UREA, 100 pingao plants Weed control (KCDC contractor) back dune plants (PB2 or tinus root trainers)

9 Area(s) Year(s) Actions Resources required C 2 Remove other exotics shrubs and plant up gaps in natives; create gaps in marram grass using weedeater and spray herbicide, then plant small groups of 3-10 native plants in each gap. B 3-5 Continue weed control and gap cutting for planting native backdune species in small groups. B, C 1-5 Ensure all plantings are maintained, particularly regrowth of weeds, before extending plantings to new areas. Fill in bare areas. Fill in areas between successfully establishing clusters of natives. Weed control (KCDC contractor) back dune plants (PB2 or tinus root trainers) Weed control (KCDC contractor) back dune plants (PB2 or tinus root trainers) Monitoring and maintence programme. Labour as required.

10 CONCLUSIONS The Peka Peka site could become a flagship demonstration area along this local coast of a restored dune profile from native sandbinders on the foredune to a wide range of native backdune species established on the undulating semi-stable rear dune including damp swales. The site could demonstrate the value of a realigned well-managed pedestrian accessway with clear accessway signs at either end. An actively managed restored dune could become an excellent environmental education opportunity for local schools. An information board placed at a vantage point along the accessway would illustrate the main points of the restored dune system for visitors imploring the need to respect the vegetation cover and keep to the formed access track provided. If well managed this could lead to an Adopt a Beach approach for local residents and beach users where restoration and management of parts of the beach and sand dunes are identified, facilitated and resourced. For example, the Surf Club taking responsibility for management of the beach and dunes immediately in front of their surf club and adjacent facilities such as carparks.