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Determination of resources / environment dynamics at an oceanic scale, a necessary integrated approach for a new management







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    Meeting
    Are Indian Ocean tuna populations assessed and managed at the appropriate spatial scale? Brief review of the evidence and implications 2013
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    Tu species maged under the auspices of the Indian Ocean Tu Commission have generally been assumed (explicitly or implicitly) to be highly mobile and consist of a single panmictic spawning population for the purposes of stock assessment and magement. In this paper, we: i) briefly review evidence that questions this assumption (largely based on recent population genetics and tagging studies), ii) qualitatively discuss the implications of violating this assumption, and iii) outline some elements of a collaborative research plan to resolve these issues and mitigate the consequences of getting this assumption wrong. This paper is intended to stimulate discussion within the IOTC scientific community about the potential importance of population structure within the Indian Ocean and extent to which it should be considered a research and magement priority.
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    Towards an Integrated Shark Conservation and Management Measure for the Western and Central Pacific Ocean 2013
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    The WCPFC has recently initiated a Shark Research Plan and adopted three conservation and magement measures (CMMs) requiring controls on finning, encouragement of live release and data provision (CMM 2010?07); no?retention of oceanic whitetip sharks (CMM 2011?04); and a prohibition on deliberately setting purse seines on whale sharks (CMM 2012?04). In parallel with these WCPFC?led shark activities, some members (CCMs) have instituted shark catch limits, established rules for no?retention of any sharks whether dead or alive, and/or banned the use of wire leaders. This current situation represents a patchwork of controls and the net benefit in terms of reduced shark mortality is yet to be determined. This paper examines three existing WCPFC shark measures in terms of their implementation and effectiveness. This alysis is complicated by a lack of specific objectives in each measure as well as a lack of verification data and review processes. Current implementation of CMM requirements appe ars to be at best ~60% and in several cases considerably lower. This is partially due to ambiguities in interpretation of the CMMs such that opposite outcomes can both be considered compliant. Extremely low regiol observer program coverage (<2%) in the longline fishery, which catches over ten times as many of the key shark species as the purse seine fishery does, further hampers assessment of effectiveness. Nevertheless, it appears that the Commission’s finning controls provide only a negligible benefit to shark survival. Lack of consistent recording of shark discards/releases will similarly impede a future assessment of the effectiveness of the oceanic whitetip and whale shark measures. It is thus concluded that although WCPO assessments have demonstrated the need for shark mortality reductions, these are not yet being delivered by the WCPFC CMMs. Protectionistic measures (e.g. no?retention whether dead or alive) adopted by some CCMs for tiol waters are fundamentally different from th e “full utilization” approach outlined in the Intertiol Plan of Action?Sharks (the basis of the cornerstone WCPFC CMM) and highlight the need for a new, integrated regiol framework in the form of a comprehensive shark CMM. By using shark fishing mortality as a single “currency”, such a framework can help to find common ground between measures adopted in different tiol jurisdictions and extend these principles into high seas areas. It can also avoid decision?making stalemates arising from one?siz e?fits?all proposals which suit some fisheries but not others. An approach similar to that used for tropical tus is proposed whereby a fishing mortality magement goal is set based on assessment results, and a package of mitigation measures designed to reach the goal is negotiated and implemented on an interim basis. Verification data are generated and retrospective alysis leads to periodic revisiting of the measure. The paper concludes with recommendations for a) improving the Commission’s abili ty to confirm compliance with the existing measures; b) maximizing the effectiveness of the existing measures; and c) creating a framework within which the effectiveness of all measures (existing or proposed) can be judged on their ability to control fishing mortality for overfished shark stocks. The WCPFC has the opportunity and the responsibility to mage highly migratory shark stocks in a comprehensive and integrated manner across the Convention Area, and must therefore take actions which are not only expedient, but also meaningful and effective.

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