On 1 December 2022, the Kaikoura pāua fishery was re-opened following a five-year closure, as a result of the impacts of the November 2016 earthquake. The re-opening process was initiated by the Ministry after a request by the Kaikōura Marine Guardians (KMG) in May 2021. This advised that the Minister should consider re-opening the fishery when specified biological criteria of pāua population recovery had been met and when appropriate management controls were in place to ensure sustainability. This was in line with Fisheries Act sustainable utilisation principles. While scientific surveys indicated sufficient population recovery for a cautious approach to resuming fishing, the package of measures to ensure that recommended by the KMG was not fully implemented.
However in this shared fishery I just wanted to give an account of how the three month initial season went for the professional pāua divers there.
In the years prior to the re-opening, PauaMAC3 (the industry organisation for the Kaikoura region) developed a comprehensive suite of management measures that they thought would ensure that any re opening would be sustainable. These management initiatives were formalised in the Ministerially approved s.11A PAU3 Fisheries Plan. One of the key moves was to ask the Minister to sub divide the PAU3 Quota Management Area into two. Pau3 became PAU3A and PAU3B. This was done in recognition of the fact that there were now two separate fisheries, the earthquake affected area to the north of Conway River, PAU3A, and the unaffected area south of the Conway to the Waitaki River, PAU3B. Each had different management requirements. Strategies in the plan were based around principles of a precautionary approach to fishing with the re-opening, and an adaptive rebuild going forward.
Industry limit their catch
The first precautionary approach to commercial fishing was for the Minister to limit the TACC (the amount of commercial catch) to half the amount of pāua that had been historically harvested commercially from the pre earthquake area (PAU3A). Within this overarching control, PauaMAC3 has established finer scale management across defined fishing zones within PAU3A to further promote the rebuild of the fishery. They are also collecting high resolution fisheries dependent data to assist with future management decisions.
The PAU3A zones have been used to implement catch spreading arrangements to control the percentage of catch that comes out of specific areas. Catch caps for each zone were established, based on research survey data from the area over the last five years and historic catch trends. Caps were set to ensure that fishing effort is not focused on the most productive areas, or areas that have been slower to recover after the earthquake. This ensures that we don’t see any serial depletion of sub populations. Harvesters are able to monitor the amount of catch that has come from each zone through the season and decide where to fish accordingly through the pāua ‘dashboard system’, a digital tool which allows for real time visualisation of catch data through an online interface.
See figure 1
Industry introduces new harvest size limit
Another significant initiative has been the implementation of a minimum harvest size (MHS) for commercial harvesters larger than the Minimum Legal Size (MLS). Minimum Harvest Sizes are implemented in the commercial fishery around the country in recognition of variability in growth and length at maturity, and the need to fish at larger sizes in some regions to ensure sustainability. In PAU3A, a MHS of 130mm and 135mm depending on the zone, have been implemented commercially. This is because best available information to us suggests that the current minimum legal size of 125mm is likely to be too small in Kaikoura, and increasing harvest size provides a further layer of protection for the recovering fishery.
Fine scale commercial catch and effort data is now collected through the Electronic Reporting and Global Positioning Reporting systems implemented by Fisheries New Zealand. These systems now allow for collection of GPS position data of vessels and diver activity, which allows for real time monitoring of fisheries health indicators through the dashboard system throughout the fishing season. The industry has also implemented a new system for monitoring the size of pāua that are coming out of the fishery using digital measuring boards, where harvesters are able to measure every pāua landed during a day’s fishing aboard their boat. This provides valuable information for stock assessment and longer term fishery monitoring. In the last season, more than 10,000 pāua were measured averaging almost 150mm, with corresponding location data for future monitoring.
See figure 2
Gumboot areas under pressure
Generally the feelings among commercial harvesters after the three month fishing season were very positive. A very high abundance of pāua was observed through commercial grounds and this was reflected in a commercial catch per unit effort (CPUE – an indicator of pāua abundance) higher than any other area in New Zealand this season. Local divers reported seeing what they always want to see, the next few years catch coming through and looking healthy. However, they do share concerns about the stock of pāua in some of the highly accessible shallow and wading depth “gumboot” areas that were subject to unusually high recreational pressure. These areas are not normally subject to commercial harvest, but they support important breeding populations that provides recruitment for the wider fishery. The narrow ribbon of intertidal and immediately sub tidal habitat is a key nursery area for pāua and is particularly vulnerable.
After five long years of the closure, the reopening last summer by Minister Parker was really welcomed. The Kaikoura and regionally based divers look forward to season two. But particularly, they look forward to seeing what the management of this amazing fishery to ensure that adaptive rebuild vision might look like.
No pressure Minister!