FAQs

  • Regardless of where you are traveling from your boat should be clean before it heads out. But it can take as little as a week for your boat to be infected with marine pests. If you are visiting an area that is known to have marine pests, and especially if you stay for a month or longer, we ask you to consider checking your boat, or informing your marina operator, mooring manager or local council marine biosecurity officer of where you have been so that they can check it if they wish to. We recommend that boats are checked both on their arrival, and a month later by which point marine pests are more likely to be visible.

  • Yes you do! Sometimes a clean hull is a better vector for marine pests, which will settle more quickly than native species on a hard, slippery surface. Please always keep in mind the possibility of carrying unwanted marine pest hitch-hikers wherever you go. ​

  • Many regions now have rules and regulations to stop the movement of marine pests.

    Most regions have Regional Pest Management Plans (RPMPs) and some of these now include marine pests. Controlled Area Notices (CANs) can also be issued for specific purposes.

    There is also a move to a nationwide approach and there are rules for all international vessels arriving in New Zealand. You can find a list of rules on www.marinepests.nz or on your local council websites.

  • Level of Fouling is a way to assess the amount of biological growth on a vessels hull. There is a 6-point ranking system. You can view the Level of Fouling document by using this link.

  • Hull surveillance is often undertaken at high risk and high value sites including marinas, moorings and anchorages. Some areas may be 100% surveyed i.e., every vessel’s hull in a certain location or harbour inspected for pests and LOF and some may only be partially surveyed. Heavily fouled vessels will be targeted as they are high-risk for spreading marine pests hitching a ride to another destination. Enforcement could include abatement and/or infringements being issued or prosecution in the most serious cases, depending on where you are located.

  • In the first instance a local haul-out can provide a boat owner the service of cleaning and also antifouling (when required). Many yacht and boat clubs also have facilities that are available to members, often at a reduced rate. It is best to clean your hull out of the water so all discharge can be collected and not enter the sea – that means all contaminants including heavy metals and marine pests. ​

  • Tidal grids are convenient for checking your keel or rudder, replacing anodes and fixing your prop.

    But they are not suitable for hull cleaning or antifouling because antifoul doesn’t have time to cure between tidal cycles, and also because scraping releases contaminants, including heavy metals and pests, into the water.

    We recommend using an approved haul-out facility instead where waste is captured and treated to protect our environment. There is a list of haul-out facilities around the country at www.marinepests.nz

  • Check with your council. In some places if there is a slime layer it is ok to clean in water, but not in any of the prohibited cleaning areas. If you already have marine pests onboard, you should use an approved haul-out facility and use a local facility so as not the spread the pests en-route.

    If you do clean in the water, best practice is to do it before you leave your mooring or berth to ensure you don’t carry marine pests with you. Only use a soft cloth and ensure that you don’t cause damage to the paint while you do so. Scraping releases contaminants like heavy metals and marine pests into the water - and the cost of cleaning this up afterwards is much higher than the cost of a haul-out.

    The rules around the different regions vary, and it is best to check marinepests.nz before you travel. ​

  • A range of antifoul paints were banned by the Environmental Protection Authority in 2013 because chemicals in them presented serious risks for both the environment and human health. There are now a range of products available, including silicon-based products, which are considered safer. But they do need to be appropriate for use of the vessel and applied using the method specified by the manufacturer. Worldwide, a great deal of research and work is going into creating more effective products and new solutions are emerging.

    Work is being undertaken by MPI and Regional Councils along with industry on a National Biofouling standard.

  • Advice on the use of antifouling paints and management of niche areas is specific to the operational profile of each vessel. Vessel owners/operators need to talk to the antifouling paint or Marine Growth Prevention Systems (MGPS) manufacturer.

    Even when vessels follow best practice by applying the correct antifouling system as per vessel operational profile, some macrofouling can still be found on the hull and niche areas. The alternative would be to engage in proactive hull management (where permitted). Particularly “clean before they leave” to places of biological or cultural significance.

    We recommend that boat owners talk to specialist paint suppliers and contractors in order to determine the best solution for their boat.

    Guidance can be found in a technical report on antifouling and managing biofouling on vessel hulls (plus niche areas). You can search for this on the MPI Publications database.

    The Environmental Protection Authority Te Mana Rauhī Taiao also provide guidance on antifouling on their website.

  • Yes, owners are responsible for cost associated with maintaining their vessels so that they comply with the rules.

  • Haul-out and cleaning facilities operate under resource consent conditions and are required to ensure any discharge meets the requirements from the clean before it makes it into the water. While this is monitored, you can also report non-compliance of discharge to the sea to your local council.

  • Yes, so long as there is acceptable proof of the works completed and EPA and HSNO Act requirements are met. Be sure to follow the antifoul manufacturers guidelines and ensure adequate drying time between coats and before putting her back in the water. ​

  • To identify marine pests, a first step is to look at the Biosecurity NZ Marine Pest ID Guide available here. If you see something unusual, please report it! You can report a marine pest by using the reporting tool on the MPI website. This page contains information about how to photograph a suspected marine pest too.

  • While there are more than many non-indigenous species already in New Zealand fortunately only a few of them are harmful. Marine pests can damage our natural ecosystems and the delicate balance of biodiversity and can cause financial losses.

    Aquaculture suffers significantly from increased costs relating to cleaning pests off farmed species and gear, managing parasites and diseases. Biodiversity and fish habitats are impacted, affecting our ability to maintain a healthy and resilient ecosystem, harvest fish and shellfish both recreationally and commercially. Marine pests such as Eudistoma elongatum (commonly called rock snot) can and do visually ruin the experience of visiting beaches and rock pools. Cultural impacts from marine pests include negatively affecting the mauri (life force) of the moana, impact on the gathering of kaimoana. Even relatively localised marine pest infestations have the potential to have significant cultural impacts. Marine industries bear much of the cost of resolving marine pest impacts.

    Fortunately, some of the marine pests that have done the worst damage internationally have not yet established themselves in New Zealand. We have strategies in place for if and when they do. ​​

  • Marinas and other fixed coastal structures do not move. Therefore, there is a lower risk in spreading marine pests to new areas as opposed to a vessel that moves to other destinations. The risk lies in the movement which allows marine pests to hitch a ride on growth (‘biofouling’) on a hull. Some marinas carry out regular cleaning to keep them pest free, but this is up to the marina owner. While there are few control tools for marine pests – extensive research is underway both here in New Zealand and internationally. This includes including the collaborative Marine Biosecurity Toolbox programme that seeks to develop more innovative management tools. The costs associated with the removal of marine pests is prohibitive mainly due to the issues associated with working in water, with limitations including access and cost of engaging divers. Preventing pest spread to new areas remains key to stopping them being introduced in the first place.

  • The Biosecurity Act 1993 allows councils to manage ‘pathways’ they identify – that is, the way pests (including marine pests) are transported from one place to another. In the marine environment, the ‘pathway’ really means boats, as movement of hull-fouled boats is the single biggest risk for marine pest transfer.

    Unfortunately, some marine pest species have invaded parts of our coastal marine area in recent years, arriving as hitchhikers on boat hulls or in the ballast water of international sea-going vessels. Nowadays, vessels coming from overseas must meet world-leading national rules to minimise their risk of bringing new pest species. However, we need to deal with some of the problematic marine pests that have already become established to stop them from spreading further.

    Research tells us that fouling on boat hulls is by far the biggest risk for transferring marine pests (up to 90%), though there are other ways these pests hitch-hike around.

    Marine farming / aquaculture-related movement of marine pests will be addressed by the National Environmental Standard - Marine Aquaculture (NES-MA). This standard will require aquaculture farms to manage their biosecurity risks, and further information relating to biosecurity management is anticipated to be released in the near future. The NES-MA can be found on the Ministry for the Environment’s website.

    Ballast water in incoming international vessels is managed by the MPI. However, there are currently no regulations to manage the transfer of ballast water between regions.

    There is also a risk of marine pests being moved on anchors and chains, and within equipment including scuba gear, fishing gear (including crab pots and dredges), residual water in cooling systems, bilge water, holding tanks (including live bait tanks) and the movement of fixed and moveable structures (such as pontoons) and plant in the coastal marine area.

    However, these risks are minimal compared to biofouling on vessel hulls – managing this is the biggest risk we face.

  • As a boatie, you probably enjoy being on the water and our marine environment. If we don’t look after it, there won’t be the variety of marine life to explore and experience, fish, or healthy environments to work, play on or swim/dive in. Marine pests can change all of this. Boat hull fouling is the main way that marine pests are transferred from one place to another.

    Protecting our coastlines is a team effort that requires all Kiwis to play their part - including government and councils, Māori, those that work on and around the water, and recreational boaties and fishers.

    Currently, costs are shared by boat operators (who undertake the activities that can worsen the spread of marine pests) and all New Zealanders, via local and central government entities.

    The Biosecurity Act sets out the Council’s functions, powers and duties in relation to pest management. These are focussed on the development and implementation of pest or pathway management plans. Section 135 of the Biosecurity Act allows for cost recovery for activities connected to the Council’s pest or pathway management plan, which includes the marine biosecurity programme activities.

  • Our marine biosecurity rules are designed to prevent the spread of marine pests that are in New Zealand to and within our region, and those that may arrive in the future. Just because a pest has already arrived in NZ doesn’t mean that it will naturally spread to all areas.

    Managing the pathways that marine pests travel on is an approach that is proven to work, and to be cost effective. For example, Fiordland introduced a Pathway Plan in 2017, and despite a large volume of visiting vessels, has been protected of all pests except for one (Undaria), which was established before its regulations came into force.

    Marine pests pose a major threat to the ecological, cultural, economic, social and recreational values of the marine environment. They can out-compete, smother, predate on or otherwise adversely affect native species and impact marine habitats, with consequential impacts on ecological, cultural, economic and recreational values. Once established, marine pests are extremely difficult to eradicate or contain and prevention methods are far more effective.

    Most marine pests are predominantly introduced to New Zealand waters by ‘hitchhiking’ on incoming vessels and can then subsequently spread through domestic vessel movements. These marine pest ‘pathways’ are typically hull biofouling (the build-up of marine organisms on hulls) and the discharge of ballast and bilge water. Scientific evidence to date indicates that up to 90% of marine pests are spread through biofouling on vessels and is the highest risk pathway.

    The border will never be 100% secure. But if something new turns up, we can stop the spread to other places, and prevention is key to stopping the spread.

  • Capacity at haul-out facilities is certainly a challenge particularly at peak times (summer). Recently we have begun encouraging boaties to book their maintenance in as early as possible, even doing it over winter if they can. A number of significant new boatyard facilities have opened for business in the last few years in the North Island, including Marsden Cove Marina’s boatyard, the new superyacht facility at Orams Marine in Downtown Auckland and Vessel Works in the Bay of Plenty. New facilities are planned for both Whakatāne and Whanganui to will assist commercial vessels in particular with boat maintenance and cleaning on both coasts.

    At the same time, boatyards are investing in new technologies and techniques to increase their efficiency and capacity. By way of example, the use of trailers instead of travel lifts, enables yards to haul-out and work on more boats at the same time. New technologies also assist different types of boats with biofouling - for example, slippery coatings for boats that are used regularly.

  • New Zealand is the first country to implement nationwide regulations to manage risks associated with biofouling on international vessels coming into our waters. As a first defence, all commercial and recreational vessels arriving in New Zealand are required to fulfil the requirements of the Craft Risk Management Standard for Biofouling (CRMS-BIOFOUL), proving they have managed biofouling on their vessels before they enter New Zealand waters. The MPI assesses the biofouling risk of a vessel prior to its arrival based on documents supplied by the operator, including evidence of continual maintenance, cleaning, or treatment to verify the vessel complies with the new rules.

    Unfortunately, from time to time, marine pests slip through the net and arrive, often in ballast water or in sea chests. Once they arrive in New Zealand, they can become established and/or move to new locations on vessels and equipment. We need a second “net” to catch those species that do arrive and prevent them from spreading further.

    Managing the pathways that marine pests travel on is proven to be an effective way to slow and prevent the spread of marine pests.

    For example, Fiordland, introduced a Pathway Plan in 2017, when there was only one known marine pest, Undaria, which had already arrived. Tutukaka is close to eradication of Mediterranean fanworm. Both are locations with a great deal of marine traffic, and a strict approach to managing marine pest -pathways, with the result that no-further pests have been found in either location.

    The success of biosecurity relies on all of us:

    Keeping our eyes open for new species and to report them to MPI if we see something that doesn’t seem right. If we catch pests early, the chances of successfully managing them or eradicating them is much higher.

    Checking and cleaning our boat hulls to reduce the risk of spreading marine pests to new areas. ​

  • The 6-or-1 rule is an extra set of protections that many marinas have opted into to keep marine pests out. These marinas require visiting boats to provide evidence that they have been antifouled in the last six months, or lifted and washed in the last month after leaving an area infected by marine pests. These protections are stricter than those set by most councils and are designed to ensure that new species are not introduced to the marinas, where they will be expensive to control and might be carried to pristine places like parts of the Coromandel Peninsula, Poor Knights or Aotea Great Barrier Island.

  • A successful biosecurity system will draw knowledge from a variety of valuable sources, including mātauranga Māori.  We work closely with many hapū/iwi in relation to marine biosecurity planning and response. This has been particularly instrumental to the response to exotic caulerpa in communities in the Bay of Islands, the Hauraki Gulf and Coromandel.

  • Marine biologists, policy specialists, compliance officers and ambassadors/educators are all getting involved with marine biosecurity. Suitably skilled scientific divers are in top demand right now. Keep an eye on Trademe jobs, Seek, Conjobs and ask your regional council marine biosecurity teams and local dive companies (in particular those that contract to councils) if any opportunities are available.

  • Most marinas are very concerned about marine pest incursions. Many, especially in pristine locations like the Coromandel, Bay and Plenty and Northland, have specific requirements over and above the regional rules. They are requiring evidence that boats have been cleaned or antifouled before they arrive - and they can and will follow up on this if there is any doubt. 

    Some marinas are unfortunately infested by pests like Mediterranean fanworm, and those close to international ports are particularly vulnerable to new incursions if any new pest slips through New Zealand’s marine biosecurity defence system. Finding ways to deal with this is the topic of extensive research in New Zealand and around the world but so far, hand removal is the only way to effectively remove Mediterranean fanworm from structures, and this is not considered feasible if there is a large amount present. Therefore, it is the responsibility of boat operators to ensure their boats are clean and free from pests before they visit new locations. It will take all of us, and we thank boat owners for doing the right thing. 

  • This will depend on a number of factors including where your boat is, how often it is used, how fast it travels, amongst other things. We recommend talking to your neighbour in your marina, your local boatyard, and to specialist paint shops, to find out what antifoul is best  for boats in the same situation as yours. 

  • The ideal situation for authorities dealing with a marine pest incursion is that it’s found early, when it is not yet well-established and is present in small numbers. This is called ‘early detection’. Often, removal is done manually, dealing with the creatures individually. It has been done successfully many times with Mediterranean fanworm, including in Tutukaka, Gisborne, Tauranga and Picton. Each incursion has required diligent checking, rechecking and surveillance. You can read about fanworm eradication in Tutukaka Marina here. 

  •  You may have seen in the media stories of ships being turned away from New Zealand at the border. New Zealand was the first country to implement nationwide regulations to manage risks associated with biofouling on international vessels coming into our waters, including ballast water. As a first defence, all commercial and recreational vessels arriving in New Zealand are required to fulfil the requirements of the Craft Risk Management Standard – Vessels (CRMS-VESSELS), proving they have managed biofouling on their vessels before they enter New Zealand waters. Biosecurity New Zealand (the biosecurity arm of the Ministry for Primary Industries) assesses the biofouling risk of a vessel prior to its arrival based on documents supplied by the operator, including evidence of continual maintenance, cleaning, or treatment to verify the vessel complies with the rules.


  • The approach currently differs between regional councils, and this is one of the reasons that councils in the Top of the North have been working towards a consistent regulatory approach. In regions with a Regional Pest Management Plan under the Biosecurity Act that includes marine pests, or if a Marine Pathway Management Plan or pathway style rules exist, there is generally a system of surveillance and enforcement in place. While several councils own and operate facilities for a variety of reasons, most haulout yards are private businesses.

  • Aquaculture New Zealand recognises the threat of marine pests and has a voluntary industry standard with biosecurity guidance and a management plan in place to protect its farmers from pests and diseases. Read more about A+ Biosecurity here.