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This study tests the impact of skids placed on scallop dredges in various habitats to reduce seabed impact; skids raise the scallop collecting bag 10-11cm off the seabed. The modified skid dredge caught more marketable scallops (Pecten maximus) per unit area, but also retained more bycatch overall and more undersize scallops. Results were habitat specific.

This study analyzes the impacts of annual temporal fishing closures of gillnet fisheries in Lake Saimaa, Finland on bycatch/recovery of the Saimaa ringed seal (Pusa saimensis) population from 1991-2021. Results show that  fishing was responsible for 26% of observed mortality and 90% of that was from gillnet entanglement, but most bycatch mortalities are likely not observed and therefore underestimated. Longer temporal coverage of annual closures would improve juvenile survival, but the coverage may be regionally adequate. 

Science Letters: In 2022, Mexican authorities placed hundreds of concrete blocks with entangling metal hooks to discourage gill net use; as a result, there has been a substantial decline in gill net use in the area, and healthy vaquitas(Phocoena sinus) have been observed. However, in order to fully protect the vaquita from extinction, more of the population's distribution area need to be protected from gill nets.

This summary study provides the  first global meta-analyses  of small- and large-scale gillnet odontocete bycatch  during 1990–2020, and estimates that annual gillnet bycatch in this timespan is 50,000 odontocetes. It highlights the need for improved management of gillnet fisheries worldwide, noting that effective methods (spatial closures, deterrent devices, gear modifications, etc.) will vary depending on region and species, such as using acoustic deterrents in river ecosystems or electric barriers in the open ocean. 

In the Indian Ocean tuna gillnet fisheries, cetacean bycatch is very high, but it is understudied and poorly understood. This paper investigates the issue and makes specific recommendations to strengthen knowledge and management: improve catch and bycatch reporting, increase research and analyses of cetaceans in the region in order to assess bycatch, revise the conservation measure adopted to address the bycatch of cetaceans in IOTC fisheries (Resolution 23/06) to include additional reporting for gillnets operating in EEZs, and expand the use of mitigation methods, such as setting gillnets 2m below the surface.

This study recorded and analyzed vocalizations of green sea turtles (Chelonia mydas) off the Caribbean island of Martinique, and identified which sounds seemed to be linked to flight, fear, and social aspects. When these recordings of sea turtles were played to wild sea turtles, they demonstrated behavioral responses (vigilance and/or escape) to the sounds they produce, suggesting that acoustic deterrents may be effective to reduce sea turtle bycatch. Sea turtles did not respond to synthetic or geophonic noises.

This article summarizes cetacean strandings along the Bulgarian coast of the Black Sea between 2010-2022. Of a total 1,528 strandings, evidence of bycatch was present in 80 animals. The presence of strandings with signs of bycatch even during the seasonal bans on turbot (Scophthalmus maeoticus) fishing suggests that illegal, unregulated, and unreported (IUU) fisheries may be operating.

 This study assesses bycatch and depredation  by sharks and odontocetes in the French Polynesian longline fishery between 2000 and 2018, and finds that less than 2% of the catch had been depredated, but shark bycatch was high (20,000 sharks annually, 0.5 shark every 1000 hooks). Conversely, odontocete bycatch was comparatively low  (13 occurrences in 18 years), though reporting may have been inaccurate. This is important as there is a plan to  double offshore fisheries production in the French Polynesia EEZ by 2027.

This is a meta-analysis that quantified the effects of 42 technical measures on the target catch and the bycatch of seabirds, elasmobranchs, marine mammals and sea turtles, evaluating which methods were most effective at mitigating bycatch of each fauna group. Overall, mitigation methods reduced bycatch while having no statistically significant effect on the target catch, and sensory-based measures (e.g. pingers, blue-dyed bait) generally outperformed physical-based measures (e.g. circle hook, larger mesh) in reducing  bycatch.

This study analyzed Chinese pelagic tuna longline observer data from 2010 to 2018 to determine catch composition of fisheries targeting bigeye tuna (Thunnus obesus) and bluefin tuna (Thunnus thynnus), as well as the status and discard rate common bycatch species. A total of 55 species were observed as bycatch, and the most common was shark species. The catch composition of the bigeye tuna fishery varies significantly from that of bluefin tuna.