Coastal Restoration Trust of New Zealand

Coastal Dune Ecosystem Reference Database

A structured decision-making approach for the recovery of kuaka / Whenua Hou diving petrel (Pelecanoides whenuahouensis) Technical Report

Author
Fischer, J.H.; Parker, K.A.; Kenup, C.F.; Taylor, G.A.; Debski, I.; Ewen, J.G.
Year
2022
Publisher / Organisation
Department of Conservation
Pages
39
Summary
The kuaka / Whenua Hou diving petrel (Pelecanoides whenuahouensis) is a taoka (treasure) to Kāi Tahu, and the wider community. With only ~210 adults remaining it is one of the rarest birds of Aotearoa New Zealand and is listed as Threatened – Nationally Critical in Aotearoa and as Critically Endangered globally. Recent research suggested that, despite the removal of invasive predators from its sole remaining colony on Codfish Island / Whenua Hou, the species has not recovered, and ongoing complex pressures continue to put the species at risk of extinction. To identify the best conservation management options for kuaka recovery, the New Zealand Department of Conservation (DOC) initiated a structured decision-making (SDM) process. During this SDM process, a rōpū (working group; consisting of representatives of the Papatipu Rūnaka, Te Rūnanga o Ngāi Tahu, DOC, Fisheries New Zealand, the fishing industry, and Environment Southland) was formed. This rōpū articulated seven values (objectives) fundamental to kuaka recovery and identified 11 potential conservation strategies (alternatives). Fundamental objectives included: maximising the number of kuaka and kuaka populations, Kāi Tahu to express rangatiratanga (sovereignty) and exercise kaitiakitanga (guardianship), minimising ecosystem impacts, maximising public appreciation, minimising costs to conservation management, and minimising impacts on fisheries. Potential alternatives included: status quo, increasing best practice mitigation of vessel-based light pollution, implementing light curfews, improving plant control, initiating competition management, and intra- or inter-island conservation translocations. The consequences for each alternative across each fundamental objective were then predicted using a variety of modelling techniques and expert elicitations, while explicitly accounting for uncertainty. Once consequences were predicted, the rōpū was able to navigate this decision-landscape explicitly and transparently using a variety of qualitative and quantitative decision-analytical tools to identify the preferred option for kuaka conservation. The kuaka rōpū identified that a combination of improved mitigation of vessel-based light pollution, increased weed and native plant control, competition managment, and inter-island translocations provided the best outcome for kuaka recovery across the multiple objectives. These components should be subjected to a stepwise implementation with the different representatives of the rōpū once adequate funding has been secured. The kuaka SDM process provided an inclusive environment among participants and facilitated a rational and transparent recommendation for the recovery of this taoka in the face of challenges, common for marine species recovery, including competing objectives, differing value judgements, and uncertainty