Mitigation Techniques

    Safe handling & release

    Safe handling and release refers to using best practice methods for dealing with bycatch species, to maximise their chances of survival after interacting with fishing gear. It can also include vessel manoeuvring to avoid taking bycatch species, for example, avoiding setting purse seines on whale sharks. Illustrated Guides and more general literature have been collected in the BMIS.

    Species Groups
    Marine Mammals , Sea Turtles , Seabirds , Sharks and Rays
    Fishing Gear
    Longline, Purse Seine, Gillnet

    Spatial & temporal measures

    Spatial and temporal measures aim to avoid or minimise bycatch by either temporarily or permanently moving fishing out of an area (e.g., time and area closures, marine protected areas, 'move-on' guidelines), or requiring that particular mitigation techniques be adopted in an area. They include fleet or vessel communication schemes, such as the Hawaii-based 'Turtlewatch', a dynamic means of avoiding bycatch 'hotspots'.

    Species Groups
    Marine Mammals , Sea Turtles , Seabirds , Sharks and Rays
    Fishing Gear
    Longline, Purse Seine, Gillnet

    ALDFG - management of abandoned, lost, discarded fishing gear

    Management of abandoned, lost, discarded fishing gear (ALDFG) refers to the management of fishing gear (onboard and deployed, e.g., FADs) and retrieval of lost gear as a means of reducing fisheries bycatch and environmental damage. Tuna RFMOs have adopted binding measures and data collection protocols, as well as encouraging voluntary measures, to address the issue.

    Species Groups
    Marine Mammals, Sea Turtles, Seabirds, Sharks and Rays
    Fishing Gear
    Longline, Purse Seine, Gillnet

    Acoustic deterrents and attractors

    Using sound to discourage or distract bycatch species from interacting with fishing gear. Auditory deterrents are not generally considered useful in reducing bycatch of seabirds, turtles and sharks, except in limited circumstances. In the main, this is because the feasibility and long-term effectiveness of an acoustic deterrent is affected by habituation. Acoustic deterrents (e.g., pingers) are used with some success for marine mammals, in particular, cetaceans.

    Species Groups
    Marine Mammals, Sea Turtles, Seabirds, Sharks and Rays
    Fishing Gear
    Longline, Purse Seine, Gillnet

    Decoys

    Shark decoys have been shown to work as sea turtle 'scarecrows', though these decoys also frightened-off target finfish species (tunas, billfish, mahi-mahi). Trials with 'Looming Eye Buoys', to deter seabirds from gillnets, are underway.

    Species Groups
    Sea Turtles, Seabirds
    Fishing Gear
    Longline, Gillnet