Traditional leaders used in fishing gears such as longlines, pound nets, gillnets and/or traps are modified with an alternative design. For example, deep water pound net leaders can be modified by replacing the top two-thirds of the traditional mesh panel leader with vertical ropes (DeAlteris et al. 2005).

Devices that use an acoustic trigger for releasing a buoy attached to submerged pots that would then float to the surface for gear retrieval. This would eliminate vertical (and potentially entangling) lines in the water column (DeAlteris 1999).

A number of devices used to disturb birds from foraging on bait. These include streamers attached to a pole suspended above the area where bait is set or placed in the water, towed buoys, and water jets (Melvin et al. 2010).

A circular hook design in which the point of the hook is perpendicular to the hook shank. Circle hooks are used widely in many recreational and commercial fisheries and recently have been shown to reduce both the hooking rate and the mortality of turtles that are hooked on pelagic longline gear. As a result of several successful field trials (Bolten and Bjorndal 2005)(Watson et al. 2005), these hooks are becoming increasingly used in longline fisheries.

Soak time is the length of time that fishing gear is submerged between hauls; reducing it appears to change bycatch probabilities (Watson et al. 2005).

Various colored rope or other vertical line material used as 1) buoy lines for crab, whelk or lobster pots, 2) end lines of connected pots or 3) end or anchor lines for gillnet systems (Kot et al. 2012).

Electromagnetic fields created in the vicinity of a fishing activity to deter interaction of non-target species with fishing gear, bait, or target species. For example, rare earth metals, such as cerium or lanthanide, are attached or imbedded into hooks (longline, hook and line etc.) in an effort to deter the incidental bycatch of sharks and rays (Tallack et al. 2009). The main prize of the 2006 Smart Gear competition run by the World Wildlife Fund was for a magnetic shark deterrent to be tested on pelagic longlines. Polet et al (2005) describe evaluations of an "electro-trawl" in which electric charges stimulated shrimp into moving upward from the sea floor into the path of the trawl mouth. In this approach, the space between the groundrope and the benthos might be increased without reducing target catch levels but decreasing the contact the trawl might have with some non-target benthic invertebrates and groundfish.

A gillnet with reduced vertical curvature (compared to nets typically used in a specific gillnet fishery), an effect produced by not using tie downs. The use of tie downs in general increases the amount of ballooning in the net. Presumably because the net hangs more vertically in the water column, non-target species are more likely to bounce off the net as opposed to becoming entangled within the net “bag” (Price and Van Salisbury 2007).

Modifications made to mobile fishing gear that fishes on the sea floor. An example would be the "Newhaven" spring tooth dredge, used in the Isle of Man queen scallop fishery. This dredge is wider and fishes higher off the benthos than what is typically used, and has a rubber lip instead of metal teeth (Hinz et al. 2009).

Objects such as rubber tubes, thick polyester rope, and chains attached to fishing nets to alert a marine cetacean to their presence using echolocation (Hembree and Harwood 1987).

Reduce the length of longline set to reduce the risk of depredation and bycatch (Tixier et al. 2010).

Methods that reduce bycatch by eliminating gear sets at the ocean surface by changing the property of fishing lines so that they are less likely to catch or ensnare animals feeding at the surface or in the mid-water column. These include devices such as setting chutes that place sets below the ocean surface in longline operations where they are less prone to seabird predation, and setting gillnets below the sea surface to reduce entanglement rates of small cetaceans (Hembree and Harwood 1987). They can also be used on longline vessels to increase the speed at which baited lines get below the water’s surface where seabird predation mainly occurs (Robertson et al. 2010). Other examples include low profile line, a kind of rope linking lobster pots that might be suspended deep enough to avoid whale entanglements but with enough floatation to lie above rocky bottoms that tend to abrade them. Weighted mainlines may also increase the sinking ate of pelagic longline gear, making it less likely to capture surface-feeding seabirds (Moreno et al. 2008). Frozen bait can be thawed before it is set in the water to increase the rate at which it sinks in longline fisheries. (The sinking rate can also be increased by puncturing the swim bladder of fish bait) (Gilman et al. 2007).

Increasing the overall tension across the surface area of net panels such as by increasing floation on the float line while simultaneously increasing the weight on the lead line (Thorpe et al. 2001).

Welded bars, netting or bungee cords placed in pot traps to prevent pinnipeds, small cetaceans, or otters from entering them and preying on the target catch (Noke and Odell 2002). This technique can also be used to reduce the mortality of bycatch species that may become trapped and drown.

These devices can vary. For example, they could consist of battery-operated lights set at different flicker rates intended to attract fish but not sea turtles (Wang et al. 2007). Other examples include the illumination of gillnets with a light source such as LED lights or chemical lightsticks (Wang et al. 2013). Deploying the shape of a major predator, such as sharks, near fishing gear. Some studies have indicated that shark shapes trigger an escape response in loggerhead sea turtles (Higgins, 2006). Rope consisting of polypropylene blended with a phosphor that glows a bright yellow-green underwater in wavelengths large cetaceans can see is another example. It glows for 48 hours after activation at an intensity a human can see readily at 20 yards (18 m). The design is based on the premise that with increased visibility cetaceans and perhaps turtles would be more likely to avoid rope entanglements at night or at depth. Current research is looking at how to maintain the glowing properties under the rigors of mechanized hauling (CWBR 2006). Opaque mesh netting can be inserted into the upper portion of a gillnet. This material is highly visible to birds and therefore deters them from becoming entangled in the net. This material is also more visible to marine mammals (Melvin and Conquest 1996).