UPDATED PRELIMINARY RESULTS OF AN ECOLOGICAL RISK ASSESSMENT FOR SEABIRDS AND MARINE MAMMALS WITH RISK OF FISHERIES INTERACTIONS

We examined a methodology for assessing potential risk of interactions between fisheries and species of special interest (seabirds and marine mammals) by applying a Productivity-Susceptibility Analysis to a data set of species distribution, biological information and fishing effort. This type of Level Two Ecological Risk Assessment (ERA) has been used across fishery management regimes to identify areas or species requiring additional management or monitoring. Our study indicated that the risk of species interactions is clustered with greatest likelihood in a few species, where there is particularly strong overlap between fishing effort and species ranges. We tested the sensitivity of the analysis to changes in weighting of distributional density, fishing data type (area or point data), and to adding a factor of population. We found the outcomes of the PSA analyses were robust to these effects. However, adult survival rates did influence the rankings, and were identified as a key parameter requiring careful estimation. Relative risk rankings within the longline, trawl, troll and set net fisheries examined indicated that Procellaria petrels, the coastal Hector’s dolphins (Cephalorhynchus spp.), giant petrels (Macronectes spp.), Pterodroma petrels, and some albatrosses carried the highest relative risk. For setnet fishing, dolphins and shags were also ranked relatively highly. We examined the small statistical areas where most risk across all species applied cumulatively. We identified areas where there is greatest potential for non-target take to be occurring and which are therefore candidate areas for intensified observer monitoring and mitigation of risks.