Sustainable fishing

Why is fishing sustainably important?

According to the United Nations, a third of fish populations are overfished, and 60% are fished to their biological limit. Our ocean is under enormous pressure from climate change, pollution and overfishing, including the problem of bycatch.

Sustainable fishing is one way to solve the problem of overfishing to ensure we have oceans teeming with life. Seafood is a primary source of protein for millions of people and fishing is vital for many livelihoods and communities.

Fishing sustainably is important to:

• Protect ocean biodiversity to ensure a healthy and resilient ocean
• Contribute to global food security
• Prevent protein demand shifting on land and causing further deforestation
• Protect livelihoods and communities that depend on fishing and seafood

Sustainable fishing for hoki in New Zealand.

What are sustainable fishing practices?

Almost all fishing can be sustainable if well-managed regardless of the fishing method or gear type. Fisheries science and effective fisheries management are important tools to ensure sustainable fishing is occurring. 

There are a lot of myths around sustainable fishing practices which oversimplify the problem and stigmatise certain types of fishing. For example, that big boats are bad, that we should only look for pole and line caught fish. These are false and it is important that we look holistically using all available science.

Examples of sustainable fisheries in Australia and New Zealand

How can sustainable fishing minimise impacts on the environment?

Fishing can impact more than just the species being targeted. If practices are not sustainable, the marine environment can be threatened by issues such as habitat destruction, lost fishing gear and unwanted catch.

Fisheries should have measures in place to reduce bycatch – this includes non-target fish and shellfish as well as marine mammals, reptiles, amphibians and seabirds. This might involve modifying gear, avoiding fishing in areas where unwanted or endangered species are known to live or migrate through, and adapting practices to minimise the risk of interactions.

For example, seabird entanglements can be reduced by setting lines and nets deeper in the ocean and fishing at night instead of during the day. Gear can also be modified to allow non-target species to escape or deter them from getting too close to nets. This includes adding exclusionary devices to allow large marine animals to escape from nets and devices such as bird-scaring lines or acoustic 'pingers' that repel marine mammals.

Fishing methods that interact with the seabed, such as bottom trawling and dredging, are considered controversial due to the risk of damage to seafloor habitats. However, these methods can be sustainable if well-managed. Research into seafloor habitats can identify vulnerable areas which should be avoided, including those with sensitive slow-growing species, such as corals. Fishers can also use lighter gear to reduce the impact of contact with the seabed and, in some cases, set nets at a depth that avoids contact altogether.

Steps can also be taken to prevent fishing gear from being lost or discarded at sea, and to reduce the impact of any gear that does become lost. This can include monitoring and retrieving lost gear and using biodegradable panels or locks on gear such as lobster pots, to allow species to escape.

How can fishing be sustainable?

Scientists work out how many fish can be safely caught without impacting the future health of the stock. This involves collecting data on the size of the stock, when and where the species spawns and how many juveniles are likely to survive into adulthood. They also assess environmental factors that may affect the stock, such as predation from other species.

Different management measures can also be implemented to protect stocks from overfishing, such as prohibiting fishing during spawning seasons and setting size limits to protect juveniles.

A key aspect of sustainable fishing also involves adopting precautionary measures known as harvest control rules, which require catches to be reduced if the stock population declines. This is particularly important when stocks are shared by several different countries and a collective effort is needed to prevent overfishing.

Fish stocks are also more abundant when targeted by fisheries operating sustainably than those that do not.

How does sustainable fishing protect the oceans?

Sustainable fishing helps maintain healthy and diverse ocean ecosystems and minimises impacts on endangered, threatened, and protected species.

All species have a unique role within ocean ecosystems and are part of a balanced food web of predators and prey. The loss of a single species due to overfishing or excessive bycatch can have a knock-on effect across the entire food web.

It’s not just fish stocks that benefit from a healthy ecosystem, it can also help the ocean regulate the climate. Carbon dioxide from the air dissolves into seawater and is trapped within different elements of the ocean ecosystem, such as seagrass, the shells of molluscs, and plant-like plankton.

Climate change is already having a significant impact on our oceans and the health of fish stocks, making sustainable fishing more important than ever.

Which fish are most sustainable?

There is no such thing as a sustainable species of fish, only sustainable populations of fish. What is sustainably fished in one part of the ocean, could be overfished in another.

When you see the MSC blue fish tick label on seafood, you can be sure it can be traced back to a certified sustainable fishery.

Find out more in our sustainable seafood guide.