ASFB Home > 2003 > Biological Invasions: Consequences for Parasites, Pathogens, Emerging Diseases, and Fisheries in the Marine Environment.

Risk Assessment Methods For Diverse Bycatch In The Northern Prawn Fishery.

Shane Griffiths, David Brewer and Roland Pitcher

CSIRO Marine Research, PO Box 120, Cleveland Qld 4163 Australia
Email: shane.griffiths@csiro.au

Under Australia’s Environmental Biodiversity and Conservation Protection Act, Australia’s Commonwealth fisheries are required to demonstrate long-term sustainability of all species impacted by their fishing practices. Australia’s Northern Prawn Fishery (NPF) has been proactive in attempting to minimise bycatch by developing a Bycatch Action Plan. However, demonstrating sustainability of its highly diverse bycatch (400+ species of fish) is a significant challenge. Stobutzki et al. (2001) devised a semi-quantitative method for determining the relative risk to the long-term sustainability of the NPF bycatch by ranking each species using a number of criteria describing their “susceptibility” to fishing (e.g. preferred habitat and catchability) and “recovery” capacity (e.g. life history characteristics and size at capture). Species having the lowest rank for susceptibility and recovery are least likely to be sustainable. However, this method has little capacity to demonstrate quantitatively the percentage of the population impacted by fishing, does not maximise the potential use of the quantitative data available for many of these criteria, and is weakened by gaps in our knowledge. A current project proposes a new approach to bycatch risk assessment in the NPF, primarily based on a more powerful use of quantitative data for each species and by including a key new criteria to assess the proportion of the population impacted by trawling across the its broader geographical range. This method can use a simple model to determine whether each species is under threat from this fishery or not. It will be an important tool for the NPF and other fisheries to determine their impact on non-target species, and allow a more directed focus for a new bycatch monitoring initiative.

Room 3 Thursday 9.40 am