Towards acoustic monitoring of a mixed demersal fishery based on commercial data: The case of the Northern Demersal Scalefish Fishery (Western Australia)

摘要: Ongoing monitoring of complex, mixed species environments is a challenging task. In this study, the potential acoustic and catch data collected aboard commercial fishing vessel, in combination with geostatistical variance estimates, are explored as means to derive information on distribution abundance key groups within selected regions. The FV Carolina M, trap vessel which operates waters off Broome, Western Australia, Northern Demersal Scalefish Fishery, was equipped Simrad ES70 echosounders, operated at 38 120 kHz. Optical recordings were also obtained, addition data, during routine operations 2014. Three regions, where both optical datasets available, for analysis. Geostatistical conditional simulations used combine density composition proportions length distributions catch. For each input 250 conducted, from individual combined sampling CVs derived. Conversion densities into estimates achieved through application target strength relationships (TS-L). Where TS-L unavailable literature particular it estimated Kirchhoff-ray mode model. equations rankin cod (Epinephelus multinotatus)(TSRC = 20 log10(L) − 79.6), triggerfish (Balistidae) (TSTF = 20 log10(L) − 77.7) spangled emperor (Lethrinus nebulosus) (TSSE = 20 log10(L) − 70.8) 38 kHz. Sampling error found be generally low (<12%) (<10%). Total CV group abundances three regions 9%–38%, similar typical reported surveys.