Pāua refers to three species of edible sea snail: the black-foot pāua (Haliotis iris), the yellow-foot pāua (Haliotis australis) and the white-foot pāua (Haliotis virginea). All three are endemic to the waters around Aotearoa New Zealand and have important cultural value to tangata whenua. Black-foot and yellow-foot pāua are harvested both commercially and recreationally, with yellow-foot only caught in small numbers. White-foot pāua is generally too small and rare to be easily collected.
Pāua inhabit shallow rocky reefs around Aotearoa New Zealand and have very localised larval settlement. Offspring are more likely to settle within the immediate vicinity, often inshore from their parent animals. Genetic studies have revealed that there are some distinct populations of black-foot pāua, separated by distance or dictated by strong currents.[1] For example, the North Island, South Island and Chathams populations are thought to be genetically distinct populations.
The pāua fishery is divided into ten QMAs although most commercial catch comes from only seven of these areas, with a combined TACC of 919 tonnes. Reported catch has been less than TACC for the past five years. The difference is reportedly accounted for by voluntary catch reductions by quota owners for a variety of management reasons.[2] In 2019, pāua exports were worth $50 million, including shell, by-product and nutraceutical sales. There is also a small but important domestic market for pāua, principally into Tāmaki Makaurau Auckland and Tāhuna Queenstown tourist restaurants.
The Pāua Industry Council is the peak industry body for pāua fishers and quota share owners. The Council is managed by a board of directors which includes the chair of each of the regional commercial stakeholder groups, PāuaMACs. All are funded by a compulsory levy on quota shares enabled by the Commodity Levy Act. The PāuaMACs tend to concentrate on regional matters while the Council provides support and deals with national level matters. Each PāuaMAC is responsible for drafting a pāua fisheries plan for its own QMA.
Pāua harvested near Kaingaroa on Chatham Island.
Pāua fisherman Nick Cameron explains the fine-scale management areas within PAU4.
Pāua in Rēkohu Wharekauri the Chatham Islands
The entire Chathams pāua fishery falls within PAU4 as described in the Fisheries Act 1996. PAU4 contributes more than a quarter to the national 720 tonnes of wild pāua that is commercially harvested.
Unlike the rest of Aotearoa New Zealand, pāua can be collected using underwater breathing apparatus (UBA) in Rēkohu Wharekauri the Chatham Islands, on the premise that it may reduce the risk of shark attack on divers.[3] The surfacing and descent of divers is thought to increase the risk of shark attack.[4] Since implementation of UBA at the Rēkohu Wharekauri the Chatham Islands there have been a number of great white shark incidents involving pāua divers, but none have resulted in injury. Prior to UBA several divers had been seriously injured by great white sharks.[2] Electronic reporting (ER) of the fishing method alongside the catch enabled this to be factored into CPUE, a good illustration of how technology changes must be factored into the CPUE calculation (see ‘The relationship between catch per unit effort and abundance’).
In 2010, fishers were concerned about localised depletion of pāua. Even though quantitative information was limited, quota owners collectively agreed to voluntarily shelve part of their ACE, thus lowering commercial harvest.[5]
Fishers were concerned about localised depletion of pāua and quota owners came together to voluntarily shelve part of their annual catch entitlement.
In Rēkohu Wharekauri the Chatham Islands the management organisation is known as PāuaMAC4. Reflecting an appropriate scale in which this resource needs to be managed within its ecosystem, there are 57 statistical sub-areas that have been adopted within the fisheries plan. These statistical areas were identified and developed in the mid-90s by the then Ministry of Fisheries to improve catch reporting. They have since been superseded by ER and GPR and are no longer used by the Ministry. As noted, industry continue to use them as a local management tool.
Species like pāua are well-suited to fine-scale management because:
- They are sedentary species that naturally tend to aggregate and are more prone to be impacted by localised fishing efforts.
- Pāua fisheries are made up of large numbers of sub-populations, with characteristics and population dynamics varying at reef or bay scale. Length at maturity and growth rates can vary greatly at scales of a few hundred metres.
- Stock information can easily be captured by industry data recording systems in real time, which allows management responses within the fishing season.
The PAU4 plan operates within the requirements of the Fisheries Act 1996 (i.e. the plan is consistent with legal requirements) and TACC settings, but also requires more stringent and detailed actions from fishers.
The plan is consistent with legal requirements and TACC settings, but also requires more stringent and detailed actions from fishers.
Key steps that are undertaken through the management plan include:
- Using the shelving of ACE to reduce fishing effort (to less than the TACC) which acts to accelerate stock rebuild when required or to raise pāua population levels to above the current Fisheries New Zealand 40% B0 population target level.
- Controlling fishing activity (catch levels) at the statistical area level, enabling catch spreading to avoid localised depletion, and changes to minimum harvest size to above the legal requirement of 125 mm which ensures that pāua can spawn for more seasons before being available for harvest than would be the case at the current minimum legal size.
Fishers are keen to see statutory support for their more stringent management plan, which can currently only be implemented on a voluntary basis. Currently fishers that do not follow management plans are not breaking the law but rather breaking contractual requirements. The consequences of this include, for example, that they may no longer be able to lease quota from a given owner, may not be able to use certain processing facilities, or may face social consequences (which are particularly relevant in small communities like Rēkohu Wharekauri the Chatham Islands).
Aside from the PAU4 plan voluntary size limits, there are other incentives to target larger pāua. Overseas markets will often pay a premium price for larger pāua. Locally, this positively impacts population size as fewer individual pāua need to be harvested to reach the TACC. So fewer pāua are taken from the population to catch the TACC. At a 10 mm harvest size increase, estimates are that 15% fewer individuals are taken.
However, targeting fewer, larger pāua may lead to unintended management signals. The longer time spent harvesting a smaller catch, is recorded as a decrease in CPUE and be interpreted as a drop in abundance when stock assessment models are run – even if the population size may in fact be growing, as observed by local divers (see ‘The relationship between catch per unit effort and abundance’). This is concerning to fishers as positive changes in the industry reflecting EAFM could potentially lead to undesirable regulatory outcomes such as TACC reduction. There is potential for similar impacts to occur in other fisheries. More responsive fisheries management that allows for local knowledge input into the decision-making process could help to prevent these undesirable outcomes (discussed in the section ‘Changing fisheries demand nimble and responsive decision making’).
Pāua are measured and meet a minimum size specific to the area in line with the PAU4 management plan.
Tom McClurg talks about the history of Chathams’ fisheries.
Consideration of an EAFM
The Pāua Industry Council is, across its regions, reviewing how they can apply an ecosystem approach to pāua management more widely.[6] Pāua harvesting has minimal direct impacts to habitat (e.g. use of blunt knife-like tools to prise pāua off reefs, light anchoring systems), has no bycatch, and no interactions with protected species such as seabirds or dolphins. Pāua are also not thought to have a structurally important role in ecosystems. Pāua mainly feed on drift algae and small amounts of attached seaweed, for example Macrocystis pyrifera, while their key predator (starfish) is a generalist and scavenger so the removal of one prey species (pāua) is unlikely to have a large impact.[6] There may be competition between pāua and kina as they are both reef grazers, and there is evidence that removing pāua contributes to the establishment of kina barrens.[7] Concerns largely centre around cumulative impacts as a whole.
Initiatives suggested in the review on how to incorporate ecosystem approaches[6] include:
- Updating diver codes of conduct through annual operating plans to suggest ways to minimise ecosystem impacts, for example avoiding anchoring near recognised recruitment habitats.
- Continuing to spread catch to minimise risk of ecosystem impacts caused by local depletion of pāua (and reduce cumulative effects) and to maintain pāua populations at a relatively high level of abundance, using the Fisheries New Zealand default of 40% B0 as a minimum target.
- Coordinating with research institutions to monitor sea temperature and ocean acidification, as well as habitat and ecosystem monitoring.
- Monitoring the abundance of pāua at different life stages, e.g. possibility of monitoring pāua recruitment using pāua ‘motels’.
- Incorporating projected environmental changes into long-term management strategies and initiatives, e.g. kelp restoration, translocation to areas of cooler currents.
- Reviewing spreading of catch in the event of marine heatwaves if there is mortality.
- Developing best practices to reduce sedimentation in near-shore ecosystems.
The PAU4 plan sets out specific management objectives, which then enable easier identification of the most important science and research needed to inform more effective management. HPSFM have been identified as a priority by the industry council for identification. The Pāua Industry Council has been tasked with work, which is now underway, to define, identify and map habitats of particular significance to pāua in all QMAs. This body of work, which is expected to be completed in 2021, can be used to inform further operationalising of an EAFM for pāua fisheries.
The PAU4 plan sets out specific management objectives, which then enable easier identification of the most important science and research needed to inform more effective management. HPSFM have been identified as a priority by the industry council for identification.
For example, once identified the industry will be able to advocate for protection of these habitats against sedimentation, dredging and debris through engagement with local council. Regional councils are obliged to take into account an existing Fisheries Plan approved under Section 11(a) of the Fisheries Act 1996 when developing their Coastal and Regional Plans. Currently (as discussed in ‘Fisheries management and land-based regulations are not integrated’) there is poor implementation of statutory requirements to integrate integration of management from the land to the sea.
Some of the Pāua Industry Council’s current management approaches are consistent with an ecosystem approach, though they are not necessarily labelled as such. The Fisheries Act 1996 provides a platform this approach to occur, building on a platform of single-stock assessment.[2]
Some of the Pāua Industry Council’s current management approaches are consistent with an ecosystem approach, though they are not necessarily labelled as such.
While this is a niche industry, it provides a good example of applying principles of community led management and a move towards an EAFM.
Reference and footnotes
[1] Will, M. et al. (2015) Broad-scale genetic patterns of New Zealand abalone, Haliotis iris, across a distribution spanning 13° latitude and major oceanic water masses, Genetica, 143(4), pp. 487–500.
[2] Input from Pāua Industry Council.
[3] Hills, J. (2015) Paua Fishery Research Programme (Haliotis iris) 2016-2021 pp. 96, Unpublished, Fisheries New Zealand.
[4] Ministry for Primary Industries (2013c) Use of underwater breathing apparatus (UBA) in selected shellfish fisheries MPI regulatory impact statement, p. 6.
[5] Chatham Island Paua PAU4 Fisheries Plan (2019).
[6] McCowan, T. (2019) Ecosystem approaches to management of pāua fisheries: Review and considerations, Pāua Industry Council Limited, pp. 19.
[7] Wing, S. R. et al. (2015) Overthrowing a regime shift: Displacement of sea urchins by abalone in a kelp forest ecosystem, Ecosphere, 6(12), pp. 1–13.