Standard Talk (15 mins) Australian Society for Fish Biology Conference 2022

Forgoing the distance: Assessing the suitability of new model-based multivariate analysis for fisheries science via an NSW ocean prawn trawl elasmobranch bycatch case study (#161)

Tom Barnes 1 2 , Daniel Johnson 1
  1. NSW DPI, Port Stephens, NSW, Australia
  2. Institute of Marine and Antarctic Studies, Kingston, TAS, Australia

The transition to model-based multivariate analysis from distance-based is important for fisheries research as this type of data is often overdispersed and therefore sometimes not suitable for traditional approaches. We present both our experience in transitioning to model-based analysis and the results of elasmobranch bycatch research (NSW ocean prawn trawl bycatch quantification as part of the Marine Estate Management Strategy Initiative 5.5). The relatively user friendly model-based analysis showed there was significant spatial differences but not seasonal and depth in elasmobranch assemblages. This result is an important early step in determining future monitoring priorities for a fishery that has a broad bycatch but has not seen regular monitoring and assessment. Importantly, this project recorded low catch rates of a diverse community of elasmobranchs with more species (and similar catch rates) recorded by the present study, than the former, which shows that the fishery is of relatively low risk to elasmobranchs.