Ecological risk assessment for the effects of fishing in the Western & Central Pacific Ocean: Productivity-Susceptibility Analysis

Citation
Kirby DS, Hobday AJ (2007) Ecological risk assessment for the effects of fishing in the Western & Central Pacific Ocean: Productivity-Susceptibility Analysis. WCPFC, Honolulu, Hawaii
Abstract

The First Regular Session of the WCPFC Scientific Committee (SC1) endorsed the suggestion (Molony 2005, Kirby et al. 2005) that Ecological Risk Assessment (ERA) be carried out for the WCPFC Convention Area. SPC-OFP undertook a preliminary ERA (Kirby & Molony 2006) based on the CSIRO/AFMA approach (Hobday et al. 2006). These results were presented to the Second Regular Session of the WCPFC Scientific Committee (SC2), who called for the continuation of this work. In December 2006 the Commission approved its budget for 2007 and a collaborative proposal to carry out the ERA work was then developed between SPC-OFP and CSIRO, Australia. This included the intention to hold an ERA Research Planning Workshop involving technical experts and relevant NGOs, and to prepare a 3 yr ERA Research Plan for submission to SC3. This proposal was subject to peer review and the WCPFC Secretariat gave their approval in March 2008. The analysis presented here is therefore a work-in-progress and there remains room for improvement in data quality/quantity and the resolution and complexity of the analyses. Nonetheless, what is presented illustrates the utilty of Ecological Risk Assessment (ERA) in supporting the Ecosystem Approach to Fisheries (EAFM) and in assisting CCMs and the SC to meet their obligations under the WCPFC Convention.
The CSIRO/AFMA approach to ERA is heirarchical (Levels 1, 2 & 3; Hobday et al. 2005): Level 1 is based on stakeholder workshops, and is designed to identify hazards to species and systems and to carry out a Scale-Intensity-Consequence Analysis (SICA). Level 2 is based on the biological characteristics of species caught in the fishery concerned, and the degree of interaction between that fishery and those species. This has been called Productivity-Susceptibility Analysis (PSA) and is the approach and level at which the ERA for the WCPFC Convention Area has so far been carried out. At this level, individual species are assigned risk scores relative to each other, resulting in a risk ranking along each of the two axes used (productivity, susceptibility) and as the distance from the origin of the graph. It is important to emphasise both the relative nature of these scores, such that they are valid only for the particular PSA carried out, and the fact that this is a risk assessment for the effects of fishing and not an estimate of extinction risk due to the sum of all risks experienced by any particular species (i.e. trophic interactions, environmental variability, climate change, fishing, habitat destruction, pollution, etc.). Estimates of population status for any single species result from analyses at Level 3, which may take the form of a classical stock assessment. ERA as a process then, is designed to engage stakeholders, identify those species at most risk from fishing activites, and ultimately to provide population assessments for those species. It is therefore a useful process for prioritisation of fisheries research and conservation/management action.