4 research outputs found
Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets.
Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called 'Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20-30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures
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Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets.
Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called 'Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20-30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures
Scallop potting with lights : a novel, low impact method for catching European king scallop (Pecten maximus)
This paper describes, for the first time, that scallops can be attracted into static fishing gear using LED lights. This novel finding presents an opportunity for the development of a new, low impact fishing method for scallops. Traditionally, wild caught scallops are primarily fished using dredges and trawls. Due to their penetrative nature, the interaction of this towed gear with the seabed can cause significant damage to sensitive marine habitats and species. Diver caught scallops have been a low impact alternative source, however, this sector can only supply limited quantities due to logistical constraints. In this study, we investigate the potential for scallops to be fished using illuminated standard commercial crustacean pots. We assessed the effect of using light in a range of pot designs on scallop, brown crab, lobster and crawfish, and spider crab catches in Cornwall between December 2020 and February 2021. A total of 77 strings were shot, deploying 1886 pots of six treatment types. The fishing grounds used in the trial are traditionally potted for crustacea and are not renowned scallop beds. Despite this, all treatments with lights retained scallops and of the 518 scallops recorded, 99.6% (n = 516) were caught in pots with lights. A modified parlour pot with lights (treatment F) caught scallops most effectively, with a maximum catch rate of 19 scallops per string (23–24 pots per string) per 24-, and the maximum number of scallops recorded in a single pot was 24. We show that simple and inexpensive modifications to existing crustacean pots present fishers the opportunity to augment their existing crustacean catches with a low environmental impact, premium scallop product. Further refinement to pot design and the lights are needed to enhance scallop and crustacean retention before a commercially viable fishery can be established. We discuss the opportunities that these new findings present to the fishing industry and marine managers
Buoys with looming eyes deter seaducks and could potentially reduce seabird bycatch in gillnets
Bycatch of seabirds in gillnet fisheries is a global conservation issue with an estimated 400 000 seabirds killed each year. To date, no underwater deterrents trialled have consistently reduced seabird bycatch across operational fisheries. Using a combination of insights from land-based strategies, seabirds' diving behaviours and their cognitive abilities, we developed a floating device exploring the effect of large eyespots and looming movement to prevent vulnerable seabirds from diving into gillnets. Here, we tested whether this novel above-water device called ‘Looming eyes buoy' (LEB) would consistently deter vulnerable seaducks from a focal area. We counted the number of birds present in areas with and without LEBs in a controlled experimental setting. We show that long-tailed duck Clangula hyemalis abundance declined by approximately 20–30% within a 50 m radius of the LEB and that the presence of LEBs was the most important variable explaining this decline. We found no evidence for a memory effect on long-tailed ducks but found some habituation to the LEB within the time frame of the project (62 days). While further research is needed, our preliminary trials indicate that above-water visual devices could potentially contribute to reduce seabird bycatch if appropriately deployed in coordination with other management measures