Evaluating active-acoustic methods for assessing snapper (Chrysophrys auratus) spawning aggregations in Western Australia

摘要: Snapper (Chrysophrys auratus) is an important commercial and recreational species, in Australia and New Zealand. From late winter to early summer, adult snapper migrate the broader metropolitan waters of Perth Western Australia into the protected embayment’s of Cockburn Sound, Warnbro Sound and Owen Anchorage to form spawning aggregations. In Cockburn Sound, they can be acutely exposed to anthropogenic (eg industry, fishing) and environmental factors (eg deoxygenation, elevated temperatures) that may affect numbers, spawning success and subsequent recruitment. Monitoring the status of these tightly-managed aggregations is particularly important as impacts of these stressors can be significant and rapid. To facilitate this monitoring, evaluation of commonly used methods for estimating spawning biomass (eg daily egg production method), against those that take advantage of developing …