Feekings, Jordan P.

Frandsen, Rikke

Madsen, Niels

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 17, 2017Diversifying the uses of the Danish Discard data collection programmeFeekings, Jordan P.; Madsen, Niels; Frandsen, RikkePublication date:2010Document VersionPublisher's PDF, also known as Version of recordLink back to DTU OrbitCitation (APA):Feekings, J. P., Madsen, N., & Frandsen, R. (2010). Diversifying the uses of the Danish Discard data collectionprogramme. Poster session presented at ICES Annual Science Conference 2010, Nantes, France.Diversifying the uses of the Danish discard data collection programmeThere is great possibility to collect additional information throughonboard observers and linking with other databases. Thisinformation can be collected at very little extra cost and effort whileat the same time diversifying its uses. It would help provide a betterunderstanding of the amounts, reasons and spatial dispersal ofdiscards, the effectiveness of current selection methods, lead tomore accurate input to stock assessments, and make it possible toassess fisheries from an ecosystem perspective. Below are somesuggestions that can obtain these objectives.Additional data to be collected onboard:• Further information on selection devices would provide knowledge asto which devices work best during actual fishing scenarios (Fig. 1). Atpresent this information is only collected through expensive gear trials(Fig. 2).• Gear information such as door spread, trawl height and mesh type/thickness would help to understand the progress of technical creepand selectivity properties better.Jordan Feekings¹, Niels Madsen and Rikke Petri Frandsen¹Corresponding author: jpfe@aqua.dtu.dkSince 1995 Denmark has collected comprehensive data on catches and discards. The programmeaims at collecting all biological information from the catch, and in addition, vessel, gear,geographical and environmental attributes. Currently in Denmark these data are used very seldomfor scientific analysis. Here we scrutinise the data and reveal pitfalls and possible additionalinformation that can improve the data quality and diversify its use into other fields of research.Fig. 2. Catch from an unselective trawl (left) and a catch from a selective trawl using a sorting panel (right).Additional data that can be collected through external databases:• Management information such as quota restrictions, and minimumlanding sizes. If quota restrictions apply, individuals (just) above MLSmay be discarded more. Quota restrictions may differ betweenvessels and can be more influential depending whether or notvessels are active in a FishPool*.• Market price. Can influence target species.• Length-weight relationships. Can be used to estimate stock losses asa result of discarding.• Different discards per unit effort can occur due to differences in yearclass strength (YCS).• Positioning as well as vessel information can furthermore beextracted from databases (VMS and vessel register) resulting atgreater accuracy and reduced work load at sea.With the reform of the common fisheries policy looming there hasbeen much discussion on the implementation of a discard ban.While a discard ban might reduce the problem it will not eliminatediscards. A loss of juveniles will still occur resulting in a loss to thespawning stock biomass and future stock size. Rather, a betterunderstanding of the issues affecting discarding is needed. Thiswould provide for much better management of the overall systemwhereby a discard ban could eventually be implementedsupplementary.Fig.1. Additional information that can strengthen the Danish discard data collection programme (clear) and data currently collected (green).Why do fishers discard?• Fish caught are under minimum landing size• Species have no/ low market value• Catch is damaged• High grading• No quota / quota exhausted• Species closureICES Annual Science Conference 2010, Nantes, France ICES CM 2010/ R:27www.aqua.dtu.dk*a FishPool is where fishers may lease and swap quota allocations even after having landed the fish.Acknowledgements: This study was conducted under the EU project: BADMINTON - Bycatch And Discards: Management, Indicators, Trends And Location 

Diversifying the uses of the Danish Discard data collection programme

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Diversifying the uses of the Danish Discard data collection programme

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