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This study examined the spatial and temporal variations in bycatch rates of four species of great albatrosses. Observer data was obtained from the Uruguayan pelagic longline fleet and Japanese vessles operating in Uruguay. Vessel operational practices and habitat variables affected bycatch rates, including: setting time, moon phase, and area and season. 

Potential risk of fisheries to cetaceans was assessed using a screening procedure based on a Productivity Susceptibility Analysis (PSA) using gears found in Ireland. Gillnets targeting demersal species was assessed as the fishery posing the greatest risk to cetaceans. Pelagic trawls targeting small pelagic species was found to pose a moderate risk to cetaceans. Specific gear-species interactions were also identified, such as humpback whales and pots/traps.  

The long-term effectiveness of acoustic pingers in reducing marine mammal bycatch was assessed in the California swordfish and thresher shark drift gillnet fishery. Bycatch was observed at sea between 1990 and 2009, with acoustic pingers being present from 1996 to 2009. Bycatch rates of cetaceans decreased by around 50% when pingers were present; the decrease was mostly driven by common dolphins. Beaked whales have not been incidentally caught since 1995. Pinger failure occurred in less than 4% of observed sets. Cetacean bycatch was 10 times higher in sets where more than one pinger failed. There was no evidence of habituation to pingers by cetaceans. Bycatch rates of California sea lions was almost double in sets with pingers than without, leading the authors to examine the "dinner bell" effect of pingers. Depredation of swordfish by sea lions was not linked to pinger use, instead the best predictors were total swordfish catch, month and area fished, and nighttime light use.   

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. 

Logbook and observer data were used to assess common bottlenose dolphin (Tursiops truncatus) bycatch patterns from 2003 to 2009 in the Pilbara trawl fishery. Dolphins were caught in all fishery areas, across all depths, and throughout the year. The bycatch rate from observers was 12.6 dolphins/1,000 trawls, which was double the rate reported in logbooks. The most significant predictors of dolphin catch were: vessel, time of day, and the use of bycatch reduction devices (BRDs). BRDs reduced catch by 45%.

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Information on the use of Dolphin Wall Nets (DWN) by fisherman in Kerala, India was presented in this paper.  The DWN was designed by these fishermen to reduce dolphin attacks during fishing operations. Specifically humpbacked dolphins tend to congregate in fishing areas, surrounding the ring seine net and removing fish from the net.  This net design can be used by fishermen instead of crackers, which can cause harm to the dolphins. The authors provided fishermen from four stations in Kerala, India (Kasargode, Kozhikode, Ernakulum and Kollam) questionnaires to fill out. The questionnaires were designed to collect information on ring seine fishing operations, dolphin attacks and the structural details of the DWN when it was used.  The authors presented results on the structure of the DWN used by these fishermen but did not report any information regarding differences in bycatch rates between regular ring net operations and those using DWN.

Incidental captures of the franciscana dolphin (Pontoporia blainvillei) by artisinal coastal fishermen of Buenos Aires, Argentina were investigated. Data was collected on carcasses of 54 incidentally captured dolphins between 2003 and 2009. Results indicated that the majority (69%) were animals four years old and younger, 74% of entangled animals were sexually immature and 85% were physically immature. Entanglements were not associated with any disease or physiological disorder. No bycatch mitigation techniques were tested for this paper.