A parasite that has the potential to harm the oyster industry has been found in Foveaux Strait but there is hope the systems in place to ensure boats and equipment are clean will help to ensure it doesn’t spread further.
On 25 March 2021, three wild oysters from Foveaux Strait were confirmed infected with Bonamia ostreae, a parasite that infects flat oysters, including New Zealand’s flat (Bluff or dredge) oysters, which can cause widespread oyster deaths.
Within five days, Ngāi Tahu and Biosecurity New Zealand enacted a rāhui and a Controlled Area Notice to the specific geographical area where the infected oysters were found, to reduce the risk of the disease spreading. Sampling of other sites is also underway.
Choosing the right antifouling coating for your boat depends on a large number of factors including how you use the boat and where it is moored, says Brent Wilson of Marsden Cove Marina. He says it’s important to talk to specialists about what you need because a product that works well on a boat in one location may not work well on the same boat in a different part of the coast.
Antifoul is considered our best line of defence against marine pests, but it's not the only option.
Antifouling coatings are still our best weapon against marine pests. But many of the traditional formulas come with unwanted side effects for our environment and health and that leaves boat owners concerned about how they can safely – and cost effectively – keep their boat protected from fouling. It’s not a challenge we face alone in New Zealand. We talk to three industry experts about how the antifoul industry is working to find solutions.
Early evidence reported by the teams surveying boats at anchor in Northland is that around 85% of boats, both local and visiting the region, are free of marine pests.
It confirms a steady increase in the number of vessels ensuring their boat’s hulls are clean and free of marine pests
“It shows that most of our boatyards and haulouts not only in Northland but in regions where visiting vessels originate are doing a great job of cleaning,” Kathryn Lister of Northland Regional Council. “Boat owners are also to be credited and thanked for understanding the need to complete this maintenance before they arrive.”
Kathryn says this is in large part due to work done in the regions, including Auckland and Bay of Plenty in both education and surveillance. For example, Auckland Council run a summer Outreach programme that sees friendly ambassadors at marinas and busy boat ramps, raising awareness with boaties and the public on marine biosecurity.
Rules were introduced to Northland in 2010 to help ensure that marine pests could not be transferred to pristine places on moving vessels. Since then, the councils involved in the marine biosecurity partnership have worked hard to educate and inform boaties about marine pests, the harm they can do, and the need to check and clean boats.
Many thousands of boats visit Northland each summer, many from Auckland. Some marine pests are prevalent in Auckland, but are not present in the majority of Northland’s harbours. Boats entering Northland or moving between the regions different harbours can have no more than a slime layer and small patches of visible fouling, according to the region’s biofouling rules.
A citizen science project has captured the curiosity of young Kiwis and is emerging as a potentially powerful marine biosecurity tool.
Marine Metre Squared – or Mm2 – encourages communities to explore what is living on their local shore and get involved in long-term monitoring by observing and recording changes on their coastlines. Mm2 is be a useful way for communities to investigate issues of local concern that may impact local biodiversity – such as the establishment of pest species. By having many eyes (and hands) searching along the coast, everyone can be on the lookout for unusual looking things, report them to their local government and aid in protecting Aotearoa’s unique coastline.
Anyone interested in learning more about the Mm2 programme is invited to visit the website here
Please add these species to your list of species to look out for:
The sea squirt Clavelina is emerging as a concern and we are working to understand more about how it may impact our coastlines. Clavelina forms large colonies on hard surfaces (including marinas and rocky shores) and also attaches to boat hulls and there is a high chance it will have the edge over native species when it comes to competing for food and space.
The sea squirt Clavelina lepadiformis has been found in several locations and is emerging as a concern because of its ability to quickly form large colonies. Clavelina oblonga is only know to be present at one site in Aotearoa; Smokehouse Bay at Aotea Great Barrier Island.
Clavelina lepadiformis is distinctive: it is called a ‘lightbulb tunicate’ because with its transparent tubes and white, yellow or pink bands, it can look like a glowing light bulb. It was recently found in Gulf Harbour and has been observed on a number of vessel hulls in regions outside of the known established populations – giving rise to concerns that it may be spread by moving vessels.
Download the Clavelina Fact Sheet here
Photo credits: Clavelina lepadiformis (c) S Happy, Auckland Council. Clavelina oblonga (c) C Woods, NIWA
The Bay of Plenty Regional Pest Management Plan 2020 – 2030 became operative in December 2020 and contains new rules to protect the region’s marine environment.
Rule 1 - The occupier in charge of a craft moving to, or within Bay of Plenty waters must ensure the hull is sufficiently cleaned and antifouled, so that the hull has no more than a slime layer and/or barnacles.
Rule 2 - All aquaculture equipment (including ropes and floats) used within Bay of Plenty waters must not have been used outside Bay of Plenty waters or used within a known pest incursion zone in the Bay of Plenty.
By directly targeting the movement of vessels and the marine industry equipment, the rules ensure that craft owners and the marine industry take responsibility for helping to stop the spread of marine pests.
Read the Regional Pest Management Plan
In a pivotal move for marine biosecurity in the Auckland Region, marine pests are now listed in Auckland’s Regional Pest Management Plan. This extends effective biosecurity protection from the land into the sea, providing vital protection to the Hauraki Gulf and its islands.
Auckland Council is introducing new rules from the Regional Pest Management Plan 2020-2030 (RPMP) that cover the entire Auckland region, and also regulations that affect those who live and visit the Hauraki Gulf and islands given effect by the Hauraki Gulf Controlled Area Notice. Through a phase in process, Auckland Council will assist commercial operators, private users and landowners within the Hauraki Gulf in understanding and complying with the rules over the next few years.
Important points from the new RPMP are:
Find out more about the Auckland Council’s approach to pest management and how you can help
Locally, regionally and nationally, the quest to prevent the spread of marine pests continues. Consultation in 2019 showed widespread support for more action to control marine pests and demand for a simple and consistent approach that is easier to understand and implement across regions. Northland Regional Council, Auckland Council, Bay of Plenty Regional Council and Waikato Regional Council, with support from the Ministry for Primary Industries and Department of Conservation, are progressing work to create an inter-regional approach that will reduce the spread of marine pests on vessels.
We now expect that formal consultation will take place in the second half of 2021, and we will keep you posted as it gets closer. Our colleagues at MPI are also working with industry to develop best practice guidance for hull cleaning and antifouling.