First Kaipara marine pest survey in more than decade

Marine pests in the Southern Hemisphere’s largest harbour are to come under scrutiny in earnest for the first time since 2006 via a joint local authority, Ministry for Primary Industries (MPI) and NIWA survey expected to begin shortly. 

The Northland Regional Council (NRC), its Auckland Council neighbour and MPI have contracted marine biosecurity experts from NIWA to carry out the weather-dependent Kaipara Harbour work, scheduled for Monday 13 to Friday 24 May.

The two councils share jurisdiction over the huge harbour and the NRC’s Kaipara constituency representative Penny Smart says the new survey is designed to boost knowledge of the current marine pest situation there, especially on and around artificial structures, which are considered ‘high-risk’ for pests.

Amélie Augé, the NRC’s Marine Biosecurity Manager says the last marine biosecurity pest survey in the 900-plus hectare harbour was carried out by MPI more than a decade ago in 2006.

“The NIWA team will be looking for a range of marine pests using a variety of methods including diver searches, crab traps, seafloor sampling and shore searches.”

Councillor Smart says survey organisers have already been liaising with some stakeholders, including tangata whenua, and will be writing to others shortly to advise them of the survey and the reasons for it, giving an assurance that known scallop beds will be avoided during any sampling.

Amélie Augé says samples of marine pests – and any other suspect animals or plants – will be collected for identification by taxonomists where their identity is unknown.

The results of the survey will be shared publicly – including with stakeholders – once all collected samples have been identified.  “At this stage, we hope to be able to do this before the end of the year.”

Councillor Smart says the survey results will be used as part of a collaborative approach to manage marine pest risks in the Kaipara Harbour by the NRC and Auckland Council.

Additional information on all aspects of marine pest surveys can be found at www.marinebiosecurity.org.nz while background on a variety of marine – and other pests (including what to do if you find one) – is available via www.nrc.govt.nz/pestcontrolhub

Coincidentally, the looming Kaipara survey comes as the country’s four northern-most regional councils (Northland, Auckland, Waikato and Bay of Plenty Toi Moana) seek public feedback as they collectively consider creating a consistent regulatory approach to marine pests.

For several years, the councils (collectively home to the country’s biggest boating populations) have been working alongside Biosecurity New Zealand and boaties from all over – have been working together to stop the spread of unwanted marine pests like Mediterranean fanworm hitchhiking on vessel hulls.

The NRC says while Biosecurity New Zealand (a business unit of MPI) manages national rules to minimise the risk of new pest species arriving on vessels from overseas, the regulations for (mainly Kiwi-based) vessels moving around within coastal waters vary from region to region.

The four northern councils think creating a consistent regulatory approach is a crucial part of respond to the growing threat marine pests pose.

A number of potential options are being considered, ranging from a requirement for a clean hull at all times, only when moving or only when moving to specially identified places, and each option has its pros and cons

If new rules were to be proposed, each council would also need to consider things like roles and responsibilities, where the costs should lie, and how these should be funded.

The northern councils are wanting to hear what their respective local communities think before advancing the hull cleaning initiative further.

A discussion document outlining the different options, including their pros and cons, can be found on the Bionet website, along with the opportunity for the public to give feedback online: www.bionet.nz

A two-month feedback period runs until Friday 24 May 2019.