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Plastic is not the biggest problem for oceans

How overfishing threatens our seas and life within them

A line of fishing vessels docked near gray calm water.

© naturepl.com / Toby Roxburgh / WWF

Plastic in the oceans is a serious and growing problem, but there’s another threat to our oceans that’s driving some species toward extinction, irreparably changing ecosystems, harming millions of marine animals each year, and jeopardizing the well-being of people who depend on the ocean for food or work. That threat is overfishing.

What does overfishing mean?

About one-third of the world’s assessed fisheries are overfished, meaning the number of fish we catch is greater than the number of fish born or hatched. When fish can’t reproduce fast enough to make up for the losses, and populations decline. If overfishing goes unchecked, these populations never recover; fish disappear from areas where they were once plentiful. And that’s where the real issues start.

Atlantic mackerel on processing line
Atlantic mackerel on processing line.

© naturepl.com / Chris Gomersall / WWF

How does overfishing impact the ocean?

Catching too many fish can abruptly break the food web, sending ripples in all directions. Predator species may decline with the lost food source; prey species may multiply unchecked. The entire ecosystem must readjust, sometimes with unpredictable consequences. Extreme overfishing of bluefin tuna might be one of the reasons we’re seeing an explosion in squid populations; it could also be contributing to toxic algae blooms.

How does overfishing impact other wildlife?

Overfishing is a symptom of poor management, and if there are deficiencies in how fishing is regulated, that could lead to an increased risk of bycatch.

Millions of non-targeted species are inadvertently trapped as bycatch each year, including sharks, turtles, seabirds, and more. It’s even the leading cause of death for small cetaceans – dolphins, porpoises, and small whales: we lose more than 300,000 to bycatch each year.

What does overfishing mean for people?

The impacts of overfished oceans even spread back to humans. Anyone who relies on fishing for their livelihood will be in trouble when the fish start to disappear.. The most extensive impacts of overfishing will be felt by coastal and island communities that depend on fish as a primary source of protein. These groups must either transition to a completely new way of life or risk pervasive malnourishment and malnutrition.

Sold tuna taken away to be delivered
Sold tuna taken away to be delivered to the buyers.

© Michel Gunther / WWF

Fresh tuna, labelled and displayed for sale
Fresh tuna, labelled and displayed for sale.

© Michel Gunther / WWF

What can be done to stop overfishing?

Considering the monumental scope of the global overfishing problem, it’s no wonder that WWF is at the forefront of innovative, collaborative solutions. WWF helped establish the Marine Stewardship Council, an easy way to identify which fish are responsibly harvested. We are preserving and expanding protected marine areas and collaborating with governments to crack down on illegal fishing. WWF even works in local communities to ensure that those who depend on fish will have a steady food supply long term. With the help of industry leaders, scientists, and fishers, we’re also finding new, practical ways of reducing bycatch.

Together we can end overfishing, keeping our oceans healthy and balanced for the long haul. And while plastic may not be the biggest threat our oceans face, you can bet we’re working on that, too.

Author: Lorin Hancock