Dr Jonathon Howard, NPA Executive member
Jervis Bay Marine Park was established by the NSW Government in 1988. It covers about 215km2 and extends from Kinghorn Point in the north to Sussex Inlet in the south. Its clear waters are due to the joining of warm water from the East Australian Current and cooler water from Bass Strait. Whales and dolphins are common sights in the marine park. It is also a popular diving and snorkelling location with an international reputation. Grey nurse sharks are regularly seen by divers at Jervis Bay. It is truly a ‘jewel in the crown’.
The marine park is divided into different zones. Aquaculture cannot exceed more than 2% (or 440 ha) of the area of the entire Marine Park and any application would be the subject of a full Environmental Impact Statement.
In recent times the park has become a focus for discussion within the NSW Marine Sanctuary Alliance. The NSW Marine Sanctuary Alliance represents community groups, marine scientists, tour operators, divers, swimmers, snorkelers, fishers and leading NGOs who share a love for the ocean and its inhabitants. The NSW NPA provides support and is one of the alliance partners.
A number of South Coast community groups who participate in the Alliance including: Our Future Shoalhaven, Keep Jervis Bay Unspoilt, Treading Lightly Inc., National Parks Association – Milton Branch, the Nature Coast Marine Group Inc., the Jervis Bay Marine Park Alliance as well as members of Jervis Bay Divers Club hold grave concerns over the infestation of mussels.
The Department of Primary Industries and Regional Development (DPIRD) and South Coast Mariculture wish to expand the mussel farm leases from 50 ha to 70ha.
Concerns are over a number of issues, but fundamentally centre around the mussel farm compromising the ecological integrity of Jervis Bay Marine Park. The evidence supporting this assertion includes:
- The species selected to be farmed can be invasive. Mytilus galloprovincialis is recognised as an invasive species in other countries. This raises a question as to whether a species with known invasive characteristics has been allowed to be farmed in a marine park. Moreover, it is a species known to hybridise with other mussel species.
- The potential loss of the locally endemic mussel species Mytilus planulatus. Mussel spatfall (the term used for young mussels) that settle on ropes, also settles on the nearby seaweed and reefs. It claims the farmed species could “outcompete other epifaunal organisms for space”.
- Connected to the above are reports of mussels in Jervis Bay in places and amounts that haven’t been seen before. For example, boat owners who keep their boats in Currambene Creek report large amounts of biofoul caused by mussel growth on their hulls and intakes. Divers are also reporting changes to the underwater low and mid intertidal zone communities. They are reporting new infestations at ‘the Docks’ and ‘Outer Tubes’.
Indeed, one diver said, “I would hazard a guess that there are now hundreds of thousands of mussels in some areas ‘downstream’ from the mussel farm, given the prevailing clockwise currents in Jervis Bay…” “We’re seeing complete coverage of reefs from the surface down to three metres and in some areas down to 8m of depths,”… “My biggest fear is 10 years down the track all of the shallow reefs of Jervis Bay are covered in an invasive species of mussel.”
There is also concern that the expansion is being ‘pushed ahead, rammed through’ as DPIRD has both a proponent and consent roles. One group have written to the Minister stating they believed “the proponent (NSW DPIRD), in its original application, did not comply with the Principles of Environmentally Sustainable Development (ESD) as defined in the Protection of the Environment Administration Act 1991”.
South Coast Mariculture (SCM) and its parent company Blue Harvest promote Jervis Bay mussels as being “carefully cultivated using sustainable aquaculture methods…” Their operations have Best Aquaculture Practices (BAP) certification which is suggested as “proof that we meet strict global standards for environmental care, animal welfare, and food safety”. In terms of the environment, BAP certification only requires implementing a standard about working within carry capacity, appropriate wild and hatchery seed supply, and managing the sediment effects on benthic communities. While the impact on the surrounding environment is considered: “Mollusk cultivation sites shall manage physical interactions with wildlife and not negatively impact the biodiversity of adjacent ecosystems”, the emphasis seems to be on predator-prey relationships, rather than wider ecosystem change due to competition for limited space on surrounding reefs.
It would appear the controversy will only be resolved once these concerns are turned into evidence. A University of Wollongong study stated there was “no proof that this spatfall was coming from the aquaculture leases” but also outlined the mussel farm spatfall was likely to seed new mussel populations in Jervis Bay. It provided strong evidence that Mytilus galloprovincialis larval supply influences the population abundance and distribution in embayments along the NSW coastline. Its author said, “that the more you increase larval load, the more you increase mussel populations”. And that there has never been any overall mapping of the wild population of mussels in Jervis Bay, but that this “would really need some scientific rigour behind it.” The Department of Primary Industries and Regional Development will also carry out genetic testing of mussels to determine if the wild and farmed stock are linked.
If you want to get involved or keep track of this issue, check out the NSW Marine Sanctuary Alliance web page: https://www.nswmarinesanctuaryalliance.org/