What is bycatch and how can it be managed?

Bycatch is fish or other marine species caught unintentionally while trying to catch another type of fish. In some cases, bycatch cannot be avoided, and unwanted fish end up in the fishing net.

Why is bycatch a problem?

Bycatch can be a problem especially when endangered, threatened and protected species such as turtles and dolphins are accidentally caught, injured or killed. Another problem associated with bycatch includes disrupting the food chain by inadvertently taking fish that other fish rely on as food. Finally, bycatch can reduce the population of a fish species to a point where it is difficult to replenish as fishing gear may not be designed to allow juvenile fish to swim free and breed. Responsible, well-managed fisheries will proactively reduce their bycatch. 

Certain fishing methods can increase the likelihood of bycatch, but effective management is key to reducing it. One such method is Fish Aggregating Devices in tuna fishing.

Read more about the problems of bycatch on the WWF website.

Can fishing with bycatch be sustainable?

Fishing activity with bycatch can be deemed sustainable so long as the amounts of bycatch are well managed and the affected fish populations remain healthy.

Most sustainable fishing will include some level of bycatch – the key is in how it is managed. When fishing activity is assessed to the MSC Fisheries Standard, scientists examine the amount and species of bycatch to see if it is environmentally sustainable.

During an assessment, the fishing managers must demonstrate that they are not threatening the population of bycatch and that they are implementing measures to minimise this unwanted catch.

What is an acceptable level of bycatch?

The acceptable level of bycatch varies depending on where in the ocean it is being caught and on the species. For example, even if the level of bycatch is low, it could be that the species is endangered, and therefore that the level of bycatch is deemed too high. Some fish can also be returned alive to the sea in an effort to manage bycatch.

How can bycatch be reduced?

Bycatch can be reduced through certification to the MSC Fisheries Standard. Fishing activity is often improved during and after certification. Improvements can include contributions to research, modifications to fishing methods or measures to build up fish populations.

If fishing managers do not comply with their certification requirements and/or no longer meet the MSC Fisheries Standard, their certificate is suspended and seafood from that source can no longer be labelled and sold with the blue fish tick

Read about how smarter fishing practices dramatically reduced the number of seabird deaths in the Southern Ocean.

Read about how the Australian Northern Prawn Fishery industry has reduced bycatch with their innovative 'Tom's Fisheye' device.

Read about how 'banana pinger' audio device trials are reducing porpoise bycatch

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Bycatch explained in 1 minute


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