Ecological sustainability of bycatch and biodiversity in prawn trawl fisheries

Abstract

Prawn trawl fisheries are under increasing public and legislative pressure to manage their by-catch sustainably, but by-catch cannot be managed without knowing what and how much is caught. This project focused on the Northern Prawn Fishery (NPF), the Torres Strait Prawn Fishery (TSPF) and the Queensland Banana Prawn Fishery. The objectives of this study were: to undertake a literature review of prawn trawl by-catch and of methods for estimating and monitoring by-catch of prawn trawl fisheries from published information to add to the already substantial literature database on by-catch reduction devices; to compile a detailed description of the by-catch in the NPF and TSPF (tiger and banana prawns) and Queensland East Coast banana prawn fisheries to provide a reference against which future assessment can be made; to measure the impact of prawn trawling on the sustainability of important vertebrate by-catch species, particularly those that may be vulnerable or endangered, and for those by-catch species for which no significant reductions can be achieved; to assess the effects of prawn trawling on the biodiversity of key fish and other vertebrate communities; and to develop cost-effective, accurate and feasible methods of describing and monitoring prawn trawl by-catch that would be acceptable to all stakeholders. The high diversity of by-catch of these tropical prawn fisheries, and the fact that most species are rare, means that managing the sustainability of the by-catch is a significant challenge.