Volume 51, No. 1

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High-contrast banners designed to deter seabirds from gillnets reduce target fish catch


1Psychology Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 7X3 *(; Current address: Royal Society for the Protection of Birds, Glasgow Office, 10 Park Quadrant, Glasgow G3 6BS, Scotland
3Fisheries and Oceans Canada, White Hills, St. John's, Newfoundland and Labrador A1A 5J7, Canada
4Migratory Birds Program, USFWS Northeast Region, 300 Westgate Center Dr., Hadley, Massachusetts 01035, USA


MONTEVECCHI, W.A., LAMARRE, J., ROUXEL, Y., MONTEVECCHI, M.W., BLACKMORE, R.J., BOURNE, C., & SPIEGEL, C.S. 2023. High-contrast banners designed to deter seabirds from gillnets reduce target fish catch. Marine Ornithology 51: 115 - 123

Received 11 July 2022, accepted 12 January 2023

Date Published: 2023/04/15
Date Online: 2023/04/10
Key words: bycatch, incidental catch, gillnets, mitigation, high-contrast banners, target catch, seabirds, Newfoundland


The incidental catch of non-target species in fishing gear (i.e., bycatch) is a global threat to sustainability and conservation in marine systems. Seabirds experience substantial bycatch mortality, with gillnets having the greatest impacts of any fishing gear. Widespread mitigation to reduce seabird bycatch in gillnet fisheries is tenuous, and information on bycatch in inshore surface-set gillnets remains a major knowledge gap. To help address these issues, we collaborated with commercial fishers to test the efficacy of high-contrast banners designed to alert seabirds. In waters of Newfoundland, Canada, banners were attached to surface-set gillnets for Atlantic Herring Clupea harengus and were compared with simultaneously unmodified control nets within the foraging ranges of major seabird colonies. The banners reduced target catch, creating a non-viable option for fishers. Seabird bycatch was low, although it may have been more substantial than indicated by local information sources. Bycatch included fish species of concern (Atlantic Salmon Salmo salar and Porbeagle Shark Lamna nasus). Owing to the episodic nature of seabird and other non-target catch, collaboration with fishers is needed to continue long-term monitoring of inshore gillnet bycatch.


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