Ecological risk assessment for species caught in WCPO tuna fisheries: inherent risk as determined by productivity-susceptibility analysis

Citation
Kirby DS (2006) Ecological risk assessment for species caught in WCPO tuna fisheries: inherent risk as determined by productivity-susceptibility analysis. In: WCPFC - Scientific Committee 2nd Regular Session. WCPFC SC2 EB-WP-1, Manila, Philippines, p 25
Abstract

Ecological Risk Assessment is a natural resource management system that recognises, among other things, the need for methods of comparative analysis for the numerous species impacted by fisheries. The 1982 UN Convention on the Law of the Sea and the various texts that derive from that, most importantly the WCPO Convention, make little distinction in terms of the management objectives for target and non-target associated and dependent species. All must be maintained at levels above that capable of providing maximum sustainable yield (as qualified by relevant environmental or economic factors); biodiversity must be preserved and ecosystem integrity maintained. There is a general acceptance that highly migratory species (UNCLOS Annex 1) are the primary group of species that the WCPO Convention and Commission have been designed to manage, yet even these constitute a long list of species, with the authority to add to this list being granted to the Commission under the Convention. Furthermore, there is an obligation to assess the impacts of fishing, other human activities and environmental factors on target stocks, non-target species, and species belonging to the same ecosystem or dependent upon or associated with the target stocks (Article 5). The list of species for which the Commission has responsibility is therefore extremely long and there is a need for the SC to develop a system for comparative analysis of target and non-target associated and dependent species. Such a system would enable prioritisation of fisheries monitoring and research effort, and potential conservation and management measures. Such a system should enable the SC and members of the Commission to meet their obligations under the Convention, as briefly outlined above.
Australia has adapted its existing fisheries management systems to incorporate a hierarchical approach to Ecological Risk Assessment. This approach is detailed in EB WP-14. Although it may appear to be very detailed and prescriptive, the general principles are simple, sound and applicable to the WCPO. At its core (Level 2) is a method for comparing the life-history characteristics and fisheries interactions of any number of species, and calculating risk scores for each species based on the most relevant biological criteria: this has been called Productivity-Susceptibility Analysis (PSA). A PSA for WCPO tuna fisheries is presented here in the hope that (a) SC2 will endorse the approach generally, as a basis for prioritisation for fisheries monitoring and research and potential conservation and management measures; (b) that further biological, ecological, and fisheries research into the key variables used in the analysis will be encouraged; (c) there will be iterative improvement in future PSAs presented to the SC; and (d) members of the Commission might carry out similar analyses for tuna fisheries operating within their zones and that they might report the results of such analyses to the SC.