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A field test was conducted to test whether harbor porpoises habitutate to pingers over time. Echolocation and movements were monitored around a mooring equipped with a pinger (Dukane Netmark 1000) for 3 months. Initial displacement was 208 m from the pinger, but it diminished by 50% within 4 days. Echolocation rate and occurrence were significantly reduced near the pinger. 

The Hawaii longline swordfish fishery reduced seabird captures through mitigating bycatch during setting. Now, 75% of bycatch occurs during hauling. Observer data was fit to a generalized additive regression model and found that density of albatrosses during hauling, leader length, and year had the largest model effects. Heavier swivels, greater than 65g, had significantly fewer catch rates for seabirds. However, heavier weights with longer leaders had reduced effects. Shorter leaders with weighted swivels closer to the hooks, significantly reduced the likelihood that baited hooks could become available to albatrosses at the surface. There was no significant difference in catch rate between hauls made with vs. without blue-dyed bait. Future haul mitigation should focus of reducing bird access to hooks as crew coil branchlines. 

The Hawaii longline swordfish fishery reduced seabird captures through mitigating bycatch during setting. Now, 75% of bycatch occurs during hauling. Observer data was fit to a generalized additive regression model and found that density of albatrosses during hauling, leader length, and year had the largest model effects. Heavier swivels, greater than 65g, had significantly fewer catch rates for seabirds. However, heavier weights with longer leaders had reduced effects. Shorter leaders with weighted swivels closer to the hooks, significantly reduced the likelihood that baited hooks could become available to albatrosses at the surface. There was no significant difference in catch rate between hauls made with vs. without blue-dyed bait. Future haul mitigation should focus of reducing bird access to hooks as crew coil branchlines. 

The Hawaii longline swordfish fishery reduced seabird captures through mitigating bycatch during setting. Now, 75% of bycatch occurs during hauling. Observer data was fit to a generalized additive regression model and found that density of albatrosses during hauling, leader length, and year had the largest model effects. Heavier swivels, greater than 65g, had significantly fewer catch rates for seabirds. However, heavier weights with longer leaders had reduced effects. Shorter leaders with weighted swivels closer to the hooks, significantly reduced the likelihood that baited hooks could become available to albatrosses at the surface. There was no significant difference in catch rate between hauls made with vs. without blue-dyed bait. Future haul mitigation should focus of reducing bird access to hooks as crew coil branchlines. 

An acoustic deterrent device (ADD) was tested at a Scottish salmon double bagnet to deter seals (grey and harbor). The ADD was randomly assigned to be on or off during observations, which were carried out from shore. When the ADD was on, there were significantly fewer seals observed and 1/3 more fish were landed per hour than when the ADD was off. Seal damaged fish were only found when the ADD was off.   

Trials of acoustic deterrent devices (ADD) were carried out on the River North Esk and River Conon in Scotland to test the effectiveness of deterring seals from a specific area of the river and as a barrier to upstream movement of the seals. The ADD was switched on and off alternatively for periods of several days and surveys were carried out to estimate the number of seals present within each river. The ADD had no significant effect on the abundance of seals in the survey area, but it did reduce seal movement upstream significantly. The reduction in movement was constant over the four month period of the trial.  

Use-intensity distributions for 135 satellite-tracked adult leatherback turtles were combined with longline fishing effort to estimate predicted bycatch risk over space and time in the Pacific Ocean. For western Pacific nesting populations, the greatest risk was adjacent to primary nesting beaches in the tropical seas of Indo-Pacific islands. For eastern Pacific nesting populations, the greatest risk was in the South Pacific Gyre. Targeted management should be based on these predicted hotspots to reduce leatherback bycatch.  

This study qualitatively describes accidents between cetaceans and fishing boats on the Brazilian coast and the Central Amazon region through the perception of artisanal fishers. From 2005 to 2010, 215 interviews were conducted. Fishers identified encounters with five species: Inia geoffrensis, Sotalia guianensis, Tursiops truncatus, Eubalaena australis, and Megaptera novaeangliae. They said accidents occurred due to animal curiosity, high speed swimming, and calve protection. The authors propose co-management with local members, researchers, and the government to encourage feelings of collective ownership within communities aiming to minimize the number of collisions. 

This study reviews existing data and information from key stakeholders on interactions between the fishing industry and seals. The data suggests that seal interactions with commercial fisheries in Ireland are most significant inshore (<12 nautical miles from shore), involves static-net (passive) fisheries (e.g. gill/tangle nets) and have increased following the driftnet ban in 2006, suggesting displacement of seal interaction from salmon to other fisheries. Pollack, angler fish, cod, and turbot fisheries were the main inshore fisheries impacted by operational damage to gear and catch by seals. The extent to which changes in fishing practices and gear has reduced damage levels is unknown.

Cory's shearwater, Calonectris diomedea, is the main seabird species incidentally caught by the Spanish longline fleet in the western Mediterranean Sea. The authors used onboard observer data to model the longline bycatch of Cory's shearwaters as a function of time of the year, technical characteristics of the fishing operation, and geographical location. The most explanatory factor for bycatch was the geographical location and then the technical characteristics (number of hooks and fishing during non-working days). Seabirds are more likely to approach longline vessels when trawlers are not allowed to operate (non-working days), so the authors conclude that activity of longliners should be limited to working days.