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This study evaluated the cetacean interactions with a bottom-set net fishery along the mainland Portuguese Southern coast (Algarve) from 2018-2022. Depredation by bottlenose dolphins occurred in 17.7% of hauls, while bycatch occurred in <1%. Depredation was elevated in the spring and winter months and in gears targeting red mullet and hake. 

This is a summary of case studies that were reviewed for efficacy of mitigation methods in gillnet fisheries for reducing seabird bycatch, focusing specifically on time-area restrictions and gear-switching. Both methods show promise to reduce bycatch and meet conservation standards, but a holistic approach that considers seabird behavior, target species  activity, and socioeconomic impacts is encouraged. Combining these methods with other measures (e.g., time-area fishing restrictions, gear-switching, visual and acoustic deterrents) may be feasible and effective in areas where if fine-scale
spatial and temporal information about seabirds and gillnet fisheries is available. 

Seabird bycatch in gillnets is a worldwide problem with few if any available mitigation 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 seabirds 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 significantly 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 field study evaluated the use of green LED handline modifications (visual deterrent) on Atlantic cod (Gadus morhua) gillnets to reduce bycatch of wolffish. Experiments were performed on three separate commercial fishing vessels in Mission Bay, Canada between September and November 2020, and experimental LED lights were applied to vessels rather than individual lines. There was no significant impact of the lights to either target catch or bycatch, but limited statistical analyses suggest that the use of green LED lights did reduce bycatch of Atlantic wolffish (Anarhichus lupus).

This field study evaluated the use of green LED handline modifications (visual deterrent) on Atlantic cod (Gadus morhua) gillnets to reduce bycatch of wolffish. Experiments were performed on three separate commercial fishing vessels in Mission Bay, Canada between September and November 2020, and experimental LED lights were applied to vessels rather than individual lines. There was no significant impact of the lights to either target catch or bycatch, but limited statistical analyses suggest that the use of green LED lights did reduce bycatch of Atlantic wolffish (Anarhichus lupus).

The present field study investigated reducing common eider bycatch in the West Greenland lumpfish gillnet fishery by a gear modification of adding a 45 cm high small-meshed net panel to the bottom part of nets. The study was trialed in the field, first in a controlled setting and then by commercial fishers, between 2021 and 2022. The modified nets displayed a 71% reduced bycatch rate for common eider and a 25% reduced catch rate for the target female lumpfish.
 

This study analyzed registered bycatch data from observer survets in the Antarctic krill fishery between 2010-2020. Total catch of Antarctic krill increased from 200,000 tonnes
to 450,000 tonnes, with the greatest increase over the last 3 years. The most dominant bycatch species were fish, followed by tunicates and other crustaceans, and the bycatch ratio was generally stable ranging from 0.1-0.3%. The highest weight of bycatch was during March–April in Subarea 48.1, February–March in Subarea 48.2, and June–August in Subarea
48.3. 

This study compiled data from National and Regional Plans of Action (POAs) and Regional Fishery Management Organizations (RFMOs) to investigate whether commercial fisheries practice the release of live sharks and rays caught as bycatch. Results indicate that onboard releases are cited in some POAs and RFMO recommendations, the measure has only voluntary adherence and is not considered priority. The authors call for a change in the perception of live elasmobranch releases as a conservation strategy.

This study analyzed records from at-sea observers covering 612,148 fishing events in the dominant tuna fisheries of the western and central Pacific from 2003-2019; this included both long line and purse seine fisheries. The result establishes a baseline of catches (both intended and non-intended) and catch compositions for industrial purse seine and longline tuna fisheries in this area, which can aid future monitoring of changing trends. Estimated catches from vessel logbooks and observer coverage both varied throughout time and were not always accurate. 

This summary study reviewed the limited supply of available peer-reviewed and grey literature from 2010 onwards to determine the impact of artisanal and commercial fisheries (by gear type) on regional sea turtle populations in NW Africa . Results suggest that all five species (green, hawkbill, leatherback, loggerhead, olive ridley) in the region are impacted, with green turtles and loggerheads showing the highest bycatch rates. Overall sea turtle bycatch is estimated to be very high, at up to 90,000 sea turtles caught per country each year, indicating that NW Africa may be a global hotspot for sea turtle bycatch.