Improving the quality of information on Scottish anglerfish fisheries: making use of fishers' data

In recent years, the International Council for the Exploration of the Sea (ICES) Working Group on the Assessment of Northern Shelf Demersal Stocks has been unable to provide an analytical assessment for anglerfish. One of the reasons for this has been the poor quality of the commercial catch-and-effort data, with ICES and the European Commission’s Scientific, Technical, and Economic Committee for Fisheries (STECF) stressing the need for reliable information on which to base estimates of stock status. In response, and following consultation with the fishing industry, an anglerfish tallybook project was implemented in Scotland as part of a long-term approach to providing better data. Tallybooks are completed on a haul-by-haul basis. Skippers record catches of anglerfish (by size category) and other species where possible, together with information on haul location, duration, and depth. Individual vessel catch rates are calculated and used to provide insights into temporal trends in the stock and the spatial distribution of the fishery. The history of the fishery and management advice are summarized, and an overview of the tallybook project is provided. Catch rates are analysed using a generalized additive modelling approach which incorporates seasonal, annual, spatial, and vessel-dependent effects. The results show increased catch rates between 2006 and 2007.