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The present study was designed to incorporate stakeholder input and fisher expertise in the design of mobulid (mantas and devil rays) bycatch technology in large-scale tuna purse seine fisheries operating in the EPO (Eastern Pacific Ocean). Surveys and focus groups of fishers suggested that the primary obstacles to mitigating mobulid bycatch are 1) inability to sight them before capture, 2) lack of appropriate response equipment on board, and 3) the difficulty of releasing large individuals. Many suggestions were made for both pre-capture and post-capture bycatch mitigation strategies.

This study used modeling to estimate Kemp's ridley and green sea turtle bycatch in major coastal fisheries across the southeastern USA from 196-2017. Results estimate that bycatch in recreational fisheries during this time was even greater than the sum of bycatch that occurred in coastal fisheries considered high risk to sea turtles, such as trawls, gillnets and bottom longlines. Despite being less abundant in the region than green sea turtles, Kemp's ridley sea turtles have higher bycatch rates in recreational fisheries, probably due to their nearshore distribution and carnivorous diet that attracts them to baited lures.

This study trialed the use of  on-demand, acoustic recovery systems/ on-demand gear (ODGs) as an alternative to vertical buoy lines (VBLs) to reduce North Atlantic right whale (Eubalaena glacialis) entanglement risk in commercial lobster and crap trap fisheries in offshore New England. Trials occurred between 2020 and 2023, and 5,798 hauls were completed using 10 different ODG prototypes. Recovery success of hauls increased throughout the trials as participants gained more experience with the gear, and fishers were able to use the gear to successfully access areas that prohibit VBLs. 

This study investigated harbor porpoise bycatch in bottom gillnets and trammel nets targeting turbot (Scophthalmus spp.) in the Black Sea between 2019-2021 via independent observers, questionnaires and stranding data. Cetaceans were caught on 55% of trips, and most were harbour porpoises. The study confirmed that bycatch is the most serious and immediate threat to the Black Sea harbour porpoises, with as many as 16,200 individuals caught annually. 

This study experimented with the use of Looming-Eye Buoys (LEBs) attached to gillnets in the Icelandic lumpfish fishery to reduce seabird bycatch, and experiments took place in spring 2022. LEBs are intended to be a visual deterrent that mimics a predator's eyes. The LEBs did not have a significant impact on target catch or bycatch, but results suggest a strong correlation between seabird bycatch and depth; the authors estimate that limiting fishing to waters below 50m deep could save between 5000 and 9300 seabirds every year.

This study investigated bycatch events in the northern South China Sea through interviews of fishers. The majority of interviewed fishers reported an estimated 7,464 annual bycatch events, with sea turtles encountered most commonly followed by Indo-Pacific finless porpoises, whale sharks, and Indo-Pacific humpback dolphins. The gear most associated with bycatch were gillnets, trawl nets, and seine nets. Modeling suggests that bycatch may be influenced by distance from the coast and water depth for marine mammals and sea turtles, but by administrative region for whale sharks.

Through fishing trials conducted in the North Sea, this study compared the bycatch reduction capacity in the Norway pout (Trisopterus esmarkii) small-meshed trawl fishery between trawls fitted with a standard sorting grid and trawls fitted with a new, more flexible system called the 'Excluder". The trawls fitted with the Excluder significantly reduced the bycatch (in weight) of nine whitefish species: blue whiting, mackerel, horse mackerel, herring, haddock, whiting, cod, European hake, and greater argentine. There was no significant difference (in weight) in the target catch, but there may be a marginal decrease in overall catch efficiency of 1.4% as some bycatch species (horse mackerel, blue whiting, greater argentine) are legally accepted and profitable in Norway.

 The present study tested LED lights in paired trials of a commercial gillnet fishery targeting Atlantic cod (Gadus morhua) in Iceland, due to previous studies that suggest attaching LED lights to gillnets to reduce seabird bycatch. The LED-equipped sets actually caught significantly more seabirds (mainly northern gannets and northern fulmars), and slightly (but statistically insignificant) reduced fish catch. While the use of LED lights on gillnets may reduce bycatch of some species, some bird species appear to be attracted to the lights.

Seabird bycatch in gillnets is a worldwide problem with few if any available mitiga-
tion tools. LED lights attached to the gillnets have been suggested as a potential solution, and a
study in Peru showed promising results where bycatch of diving seabirds was reduced by adding
LED lights to bottom set gillnets. In this study the potential bycatch reduction of LED lights was
tested in a set gillnet fishery that targets Atlantic cod Gadus morhua in Iceland. A variety of sea-
birds such as common guillemots, cormorants, eiders, northern gannets, northern fulmars, and
gulls have been observed as bycatch in that fishery. In a paired trial, nets with and without LEDs
were fished off a commercial gillnetter in western Iceland. The LED-equipped net sets caught sig-
nificantly more seabirds while a slight but statistically insignificant reduction in fish catches was
also observed. The seabirds caught in the LED-equipped nets were mainly northern gannets and
northern fulmars, plunge- and surface-feeding birds, which seemed to be attracted to the lights
while hauling and setting the nets. Caution should be taken when implementing the use of LED
lights on gillnets or trawls as while they might reduce bycatch of some taxa of diving seabirds or
sea turtles, it is possible that some bird species or groups of bird species are attracted to the lights,
in particular during hauling and setting of the nets.

This study attempts to develop a global dataset of longline fisheries using four years of GPS data from the global longline fleet in order to reduce bycatch of seabirds such as albatross. Results show that over 40 % of the ocean is, at least annually, within 30 km of a set, and this is the distance within which an albatross can detect a vessel. Additionally, the vast majority at sets occur during daylight hours even though setting hooks entirely at night is an effective way to reduce albatross bycatch, and night setting is lower than suggested from on-board observer programs. Furthermore, vessels in albatross habitat regularly set during dawn, which is when albatross bycatch risk is highest.

This study summarized data from bycatch of marine birds in Alaska salmon gillnet fisheries from 1990-2013 in order to model and estimate bycatch rates. Bycatch was highly variable by area and year, but common murres (Uria aalge) and marbled murrelets (Brachyramphus marmoratus) were highest, and longer soaking time indicated higher likelihood of seabird bycatch. The authors suggest the following practices to reduce seabird bycatch: tending nets more frequently, ensuring nets remain clean and under tension, and reducing/stopping effort during night and twilight.