Overfishing, pollution, climate change, and other problems caused by human activity are having a devastating impact on the world’s fish.
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Overfishing
Pollution
Climate change
Sport fishing
Fish farming
Aquariums
Overfishing: a net loss for the planet
It has beenestimatedthat between 0.79 and 2.3 trillion fish are caught globally from the wild each year (2007-2016). According to the United Nations Food and Agriculture Organization (FAO), more than 34 per cent of fish in the world’s marine fisheries were classified as overfished and nearly 90 per cent of the world’s marine fish stocks are now fully exploited, overexploited or depleted.
An estimated 80 fish species have gone extinct in recent centuries and more than 3000 are threatened with extinction.
Bottom trawling: a large net with heavy weights is dragged across the seafloor, scooping up everything in its path and damaging sensitive marine habitats.
Longlining: Boats use lines that can extend for up to 50 miles, with thousands of baited hooks branching off from the main line.
Industrial fishing methods result in bycatch, the unintentional capture of non-target species, which can include dolphins, sea turtles and diving birds. Animals unintentionally caught in nets often die by suffocation, starvation, or drowning.
Pollution: trashing the oceans
Pollution in the oceans, especially plastics, is a major threat to fish. Ten million tons of plastic is dumped in the ocean every year. Tiny particles known as microplastics are eaten by fish species that are consumed by humans.
Abandoned fishing gear is a major ocean pollutant, often entangling and killing marine life.
Waste from factory farms, which flows down rivers into the sea, creates “dead zones” in the ocean where fish and other marine life cannot survive.
Climate change: fish feeling the heat
Climate change is causing sea temperatures to rise. This results in acidification and reduced oxygen in the ocean, which make it more difficult for fish to survive.
Sport fishing: hooks hurt
Sport or recreational fishing is harmful to fish, as the use of hooks causes pain and tissue damage when they are caught. Recreational fishing can also be environmentally damaging. Some fish suffer barotrauma, which causes extreme internal injuries from being pulled from deep waters to the surface quickly.
“Injuries sustained during fishing cause about 18 percent of these fish to die after they are released back into the water. Among the fish who don’t die, 22 percent have their vision permanently impaired.”
Fish farming: the factory farms of the sea
Fish farming, also known as aquaculture, involves raising fish in enclosures to be sold as food. Much like factory farms on land, these farms keep fish in crowded conditions that prevent them from engaging in natural behaviours. The conditions can be stressful for fish and leave them vulnerable to disease. To prevent diseases, fish farms depend heavily on antibiotics, which can contribute to drug-resistant infections in humans.
Fish farms can also spread disease to wild fish. In British Columbia, salmon farms are being phased out because of the threat they pose to wild salmon.
Content warning
The following video contains graphic scenes depicting the inhumane conditions and slaughter of factory farmed fish.
Aquarium fish: the “dark hobby”
Keeping tropical fish in a home aquarium may seem benign but there is a dark side to this hobby and the trade that supports it. The aquarium fish industry uses methods that include using dynamite or poison (cyanide) to stun saltwater fish and collect them from surface. As many as 90 percent of fish caught with cyanide die before they reach the stores that sell tropical fish.
There are ethical questions about keeping “ornamental” fish, including whether it is right to keep these sentient creatures in small tanks when their natural habitat is the open ocean.