Abstract
Centralising fisheries management in large scale governing bodies can result in overexploitation of resources due to mismatches in bioecological and managerial scales. Further, removal of access and management rights from Indigenous communities can result in loss of cultural keystone species and associated Indigenous customs. Management of pāua (blackfoot abalone, Haliotis iris) in New Zealand exemplifies this transition. Authority over small-scale fisheries, historically managed by Indigenous communities, has been assumed by government-led regulation at scales exceeding that of individual pāua populations. This has contributed to the overexploitation of a culturally, commercially, and recreationally important species, simultaneously threatening Indigenous practices, values, and identities. Co-management can address degradation of biological and cultural diversity by returning management to local scales and authority to local people. New Zealand’s fisheries legislation aims to facilitate such a devolution through the establishment of customary fisheries management areas. Kāti Huirapa Rūnaka ki Puketeraki, a subtribe of Kāi Tahu, established one such area - the East Otago Taiāpure - in 1999, and have since strived to restore pāua through monitoring and management at a reef scale. This thesis supported these efforts by, firstly, resurveying long-term pāua monitoring sites and, secondly, trialling a restoration strategy that incorporated scientific, local, and Indigenous knowledge.
Surveys of pāua and habitat at 41 sites along the Otago coast revealed pāua density was higher inside the Taiāpure than at nearby reefs outside the Taiāpure, demonstrating the success of the management committee’s initiatives in this region. At sites within the Taiāpure, the long-term efficacy of several management measures was assessed using density data from the past 13 years. Density of pāua had declined at reefs that had remained open to fishing, despite a reduction of bag limits from 10 to five per person per day in 2010. This decline demonstrated the inadequacy of bag limits as a tool for controlling total fishing effort. Reefs closed to fishing exhibited greater densities, yet trajectories differed. Stability of pāua density within a decade-long closure indicated that removal of fishing pressure alone has been insufficient to allow recovery. Conversely, at a nearby reef closed to fishing for five years, density had increased significantly, demonstrating the small scale variability that is typical of pāua. It is likely that this small scale variation is driven by a number of interdependent environmental variables, including macroalgal composition and predation pressure.
To assist recovery, a restoration strategy was designed and trialled, incorporating recommendations from peer-reviewed studies and local and Indigenous knowledge. Three hundred and sixty pāua were translocated away from a site subject to sand inundation to a historically important yet depleted site, where movement and survival were monitored. Artificially created aggregations dispersed rapidly; by week two pāua density had declined to pre-translocation levels and mortality reached 8.8 %, attributed to predation by seastars (Astrostole scabra). Applying multiple knowledge bases in the methods’ design allowed an adaptive, locally relevant approach to conducting scientific research in the context of customary management. This was enabled by New Zealand’s fisheries legislation; translocations were carried out during a fishery closure and were permitted via an authorisation issued by customary managers as opposed to institutionally led research using a University Special Permit.
Despite demonstrated strengths of customary fisheries management areas, wider governance structures and existing legal frameworks can impose limitations on local efforts. Lastly, this thesis explored constraints to customary management in the context of two proposals made by the management committee. An application to return pāua harvesting to a customary method (wading) was not supported by the Ministry responsible for fisheries, exemplifying challenges posed by conflicting worldviews, inequitable power sharing, perceived inferiority of Indigenous customs, requirements for conventional science, and bureaucratic processes. The committee also considered incorporating Indigenous knowledge associated with the Māori lunar calendar into their management. Interviews were conducted with the local community, following a decolonised approach for non-Indigenous researchers working within Indigenous spaces, to consider how this knowledge could be applied and what constraints may be posed to doing so. Although its integration may be possible via a fishery closure and issuance of customary harvest authorisations, implementing closures has thus far only been successful for biological conservation once a fishery is in a state of decline, and not solely for implementation of customary management measures for a healthy fishery.
This thesis demonstrates the bioecological and cultural benefits that can be achieved via New Zealand’s customary fisheries management areas, yet also highlights the requirement for continued legislative transformation to enable better recognition of Indigenous knowledge and practices and, in doing so, restore pāua populations and the broader cultural values pāua and pāua harvesting represent.