New Zealand has one of the world’s largest Exclusive Economic Zones (EEZ) compared to its land area, and our ocean provides vital social, cultural, economic and environmental benefits. However, we know relatively little about our seas, particularly the coastal areas that are most important to anglers. Commercial fishers cop a lot of flak in New Zealand, but some parts of the industry are doing good things to help us better understand our coastal environment so we can continue to manage it sustainably.
One of those organisations giving back is the CRA 2 Rock Lobster Management Company, the representative commercial stakeholder group for the rock lobster fishery that extends from Te Arai in the north, through the Hauraki Gulf and the Bay of Plenty, to East Cape in the south. Aside from mandatory reporting for MPI, commercial fishers in CRA 2 invest and participate voluntarily in some important research.
The Moana Project is a five-year ocean research project spearheaded by the oceanographic division of the New Zealand MetService. It aims to improve understanding of coastal ocean circulation, biological connectivity, and marine heatwaves to produce information that supports sustainability and how we manage our marine environments.
The unique aspect of the Moana Project is that it utilises fishing vessels, with the CRA 2 fleet playing a key role, as observation platforms that collect data. Here’s how it works: sensors are installed on fishing gear such as craypots. While the gear is submerged, the sensor records temperature and depth very accurately, and when it surfaces, the data is automatically sent to the cloud via a solar-powered deck unit. From there, the data is quality-checked and incorporated into the Moana ocean models in near real-time.
The Moana Project produces a range of outputs of value to different ocean stakeholders. These observations are incorporated into hydrodynamic ocean models that allow us to better understand ocean temperature, salinity and currents, and the reasons they change. The tools will also allow the tracking of kaimoana larvae and other particles within our seas, including in great detail in the Bay of Plenty and the Hauraki Gulf. The data is managed by NIWA and is available for anyone to use.
New Zealand has earned its reputation as the marine mammal capital of the world because of its abundance of marine mammals. The Department of Conservation (DOC) is responsible for the protection, conservation, and management of all marine mammals, but doesn’t have the resources to track marine mammals by itself. CRA 2 fishers are regularly on the water and have a policy to report all marine mammal sightings to DOC, recording the species, number, time, and location. Reporting marine mammal sightings helps better determine population sizes, breeding rates, and movement patterns. Sightings reported directly to DOC or to the SeaSpotter app are recorded in a DOC database of marine mammal sightings from all around New Zealand.
CRA 2 fishers have been undertaking voluntary data collection for over 20 years. Fishers collect data from a sample set of their pots on every fishing trip. The data collected is comprehensive and includes:
This data is crucial to providing accurate results from the CRA 2 stock assessment models; without such information, the status of crayfish in the Hauraki Gulf and Bay of Plenty would be almost impossible to assess with any level of certainty. This work is fully funded by the CRA 2 commercial fishery and the investment totals over $700,000 so far.
CRA2 commercial fishers provide crucial data for the Moana Project through sensors in craypots.
Another important input into the stock assessment process, which is also fully funded by the CRA 2 commercial fishery, is the tag-recapture programme. This data allows for the accurate assessment of growth rates and migration behaviour.
The programme involves tagging and releasing crays and recording the sex, tail width and release position. If tagged critters are recaptured, CRA 2 fishers record the recapture location, tag number and tail width, and then release them to allow continual growth measures to be recorded.
There can never be enough data collected about any fishery, so if you are approached by a research provider such as NIWA to take part in a recreational fishing survey we encourage you to do so. Simply put – the more information available, the better crayfish can be managed.
Work is being done on developing an easy-to-use mobile app that will allow recreational fishers to also collect data and take an active role in helping to manage Kiwi fisheries.
If you see marine mammals while you’re out enjoying the briny, remember to report your sighting to DOC or through the SeaSpotter app.
Finally, keep an eye out for tagged crayfish. The tags are typically placed between the carapace and the tail. If you find a tagged lobster, please record:
Tag recapture work allows for the accurate assessment of growth rates and migration behaviour.
We encourage all fishers to please release any tagged lobster that you catch.
Happy fishing out there, and visit the NZ Rock Lobster Industry Council website for further information here.
- CRA 2 Rock Lobster Management Company