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A literature review of 30 studies was conducted to determine the  effectiveness of various bycatch reduction devices for elasmobranchs. The risk of capture was 1.2 times higher on circle hooks but haulbaulk mortality as well as deep hooking was reduced. Wire leaders had higher shark catch and haulback mortality rates compared to monofilament. Hooking position is determined by the hook shape and width combined with bait. These characteristics also affect the ability to sever monofilament leaders. Shark catch rates and deep hooking were increased when fish was used for bait compared to squid. Wider hooks resulted in reduced pelagic stingray (Pteroplatytrygon violacea) catch and mortality.

Threatened common bycatch species in the Baltic Sea and North Sea include harbor porpoise (Phocoena phocoena), common eider (Somateria mollissima) and velvet scoter (Melanitta fusca), as well as the non-threatened grey seal (Halichoerus gryphus) and harbor seal (Phoca vitulina). Interactions primarily occur in static net gear, such as gillnets and trammel nets, mainly used by coastal small-scale fisheries. Although technical bycatch mitigation methods are available for most fishing gears interacting with cetaceans and seals, measures focused on mitigating seabird interactions with gillnets are limited.

A retrospective analysis evaluated how mitigation measures in Hawaii (U.S)'s shallow-and deep-set longline fisheries influenced the probability of interaction and disposition (alive v. dead) of Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses. Most mitigation measures efficiently reduced seabird bycatch, however, few influenced whether interactions were fatal. In the shallow-set fishery, side-setting and stern-setting proved equally effective. Night-setting is highly effective at reducing interactions, though interaction and mortality rates were much higher during the full moon, when most shallow-set effort occurs. The use of blue-dyed bait and strategic offal/bait discharge were associated with increased interactions. 

This study investigated how flatfish interact with pot entrances, employing European plaice (Pleuronectes platessa) as a model species. Behavioral trials in a net-pen were conducted to observe plaice interacting with different pot entrance designs. Pot entrance position played a key role in plaice interactions with the gear. Low entrances near the seabed facilitated entry, while higher entrances reduced exit probability. Entrance size  and the presence and position of funnels had little effect. 

This study evaluated a novel experimental bottom trawl equipped with a double-wheeled footgear developed for the inshore northern shrimp (Pandalus borealis) fishery in Atlantic Canada. The gear combines two rockhopper disks per unit, aligned with the towing direction, aiming to reduce seabed impact while maintaining catch efficiency. Catch rates and size selectivity for target species were similar to traditional trawl gear, however, the experimental trawl produced significantly higher bycatch of juvenile groundfish, and captured more sea pens (Order Pennatulacea), providing evidence of unintended seabed disturbance. 

Monkfish (Lophius sp.) in the US mid-Atlantic and northeast are targeted through sink gillnets that also capture Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus). Large-mesh gillnets are required to fish seasonally using tie-downs as part of the Harbor Porpoise Take Reduction Plan. This study looked at the effects of tie-downs (control: 12 meshes x 30.5 cm stretch mesh with four mesh tie-downs, experimental: same, no tie-downs) on Atlantic sturgeon and marine mammal bycatch. Atlantic sturgeon bycatch (CPUE) did not differ between gillnet configurations. The experimental gillnets without tie-downs significantly decreased monkfish landings and resulted in common dolphin (Delphinus delphis) mortalities.       

Wisconsin-type fyke nets were modified in an effort to reduce the incidental bycatch of turtles, without significantly reducing the catch of targeted fish species.  The tests were conducted in three rivers (Missouri, Mississippi and Gasconade) in Missouri (United States).  The net was modified by adding four lines in the vertical gap of the net and this modification was successful at significantly reducing turtle bycatch with no significant decrease in the quantity of fish caught.

Three modified hoop-net designs were tested in the Gasconade and Osage Rivers of Missouri (United States) to determine their ability to reduce turtle bycatch without reducing the capture of targeted catfish (Pylodictis olivaris).  The three designs included an excluder net with tightly spread mesh and a sewn in ring, a chimney-set design and a loose-weave design.  The chimney-net design was the only one that significantly reduced turtle bycatch (84%), while not decreasing the number of average size of flathead catfish.

Modified trap openings were developed to reduce juvenile rockfish bycatch (Sebastes sp.) in British Columbia (Canada) spot prawn (Pandalus platyceros) traps. Smaller trap openings had no impact on rockfish or other non-target species bycatch. A novel bent tunnel opening resulted in no rockfish bycatch and the exclusion of other fish species. However, all trap modifications resulted in reductions in prawn catch rates. Large prawns were also excluded more than small prawns.