Using bycatch data to inform ecosystem-based fisheries management: a case study of a Scottish Nephrops trawl fishery in receipt of MSC accreditation

• Main Author: Glendinning, Muir
• Format: Thesis
• Language: English
• Published: 2012
• Subjects: QL Zoology; atlantic cod
• Online Access: http://theses.gla.ac.uk/3482/; http://theses.gla.ac.uk/3482/1/2012glendinningmscr.pdf; https://eleanor.lib.gla.ac.uk/record=b2937996

Eco-labelling schemes that focus on sustainable fisheries have the potential to influence behavioural changes in fishing practices, which hopefully lead to the long term goal of productive, environmentally sound and sustainable fisheries. This thesis presents a case study of a Nephrops trawl fishery. Despite being a bottom trawl fishery, it has been certified as sustainable and well managed by the Marine Stewardship Council (MSC), a leading wild capture fisheries certification programme for sustainable seafood. In addition this thesis presents an overview of seafood eco-labelling schemes and discusses how bycatch data obtained through a partnership between science and industry can inform fisheries management. The research on the fished ecosystem comprised an analysis of random sub-samples received from the fleet of certified trawlers. This involved evaluating a self-assessment scheme that was initially implemented to provide additional bycatch data across the whole fleet. Analysis showed that the scheme could produce robust results, conditional on the quantity and quality of the sub-samples collected by the fishermen being maintained at specified levels. Biological processing of the sub-samples also allowed the establishment of an extensive database, quantitatively detailing the amount of bycatch typically produced by a Nephrops trawl vessel in the region. Overall, the bycatch represented 37% of the whole catch by weight, with low catch rates of two sensitive species, Atlantic cod and Spurdog being recorded. The results from analyses of these sub-samples compare well with those from previous studies on this fishery in which the entire catch had been analysed. Similarity of the catch compositions found in the sub-samples also suggests a high degree of uniformity in the fishing process across this fleet. Two small studies on spurdog survivability and on fishing gear interactions with the sea pen Funiculina quadrangularis provided biological information relevant to satisfying the conditions of certification. This case study highlights how the MSC approach can be an effective tool for fisheries management and has the potential to generate more benefits than current non-participatory legislation.