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Information on seal bycatch in Irish fisheries were collected through an onboard observer program. The gillnet fishery had no observed bycatch of seals. Grey seals (Halichoerus grypus) and harbor seals (Phoca vitulina) were caught as bycatch in large mesh tangle nets targeting crawfish (Palinurus elephas). The west and southwest coasts of Ireland have a high risk for seal bycatch in crawfish fisheries due to the presence of grey seal colonies and similar habitat preferences.

The elasmobranch assemblage associated with the shrimp trawl fishery operating along the Pacific coast of Costa Rica was assessed. Trawl hauls were conducted between August 2008 and August 2012, resulting in the sampling of 4,564 elasmobranchs from 25 species and 13 families. The most commonly caught species (66% of the elasmobranch abundance) included the Panamic stringray (Urotrygon aspidura), rasptail skate (Raja velezi), brown smoothhound (Mustelus henlei) and witch guitarfish (Zapteryx xyster).

Six different acoustic pingers and signals were tested at sea to determine their impact on dolphin behavior. Two prototype devices from the Board Iascaigh Mhara (BIM) were tested. One was a continuous pinger (CP) and the second a responsive pinger (RP). These were tested on five occasions. A third modified RP was also tested on five occasions and a fourth RP was modified into a multiple signal output device and tested on 15 occasions. In addition, the CETASAVER and Dolphin Deterrent Device (DDD) were tested on five and ten occasions respectively.

Field testing was conducted  in the lower Bay of Fundy during 1996 and 1997 to determine the effectiveness of acoustic alarms (Netmark 1000) in reducing bycatch rates of harbor porpoises in gillnets. Alarms were spaced 100 m apart along the gillnet float-line. There was a 77% reduction in bycatch of harbor porpoises in nets equipped with alarms compared to those with no alarms. There were no significant differences in catch rates of target species, Atlantic cod, Atlantic herring and pollock. 

Four commercially available pingers (AIRMAR, Aquamark 100, Fumunda, Save Wave Saver) were tested on vessels operating in Cornwall targeting hake with gillnets. Pingers were tested for their effectiveness at reducing incidental interactions between the gillnets and porpoises. Only one of the four tested pingers, AIRMAR, performed 'satisfactorily'. 

A study was conducted in Sundarbans mangrove forest of Bangladesh to assess the behavioral response of Ganges River dolphins to pingers. Just under 62 hours of theodolite tracking data from 75 dolphin sightings and 2,829 theodolite fixes of dolphin surfacing were analyzed. The results suggest pingers had a subtle displacement effect on the dolphins. There was an increase in the mean surfacing distance of dolphins from the pinger buoy within a 100 m radius. Pingers did not result in a decrease in the minimum distance of approach for dolphins.