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EveryFish

Invasive

Fish spread outside their home range where they cause harm. 24 fish on EveryFish so far.

An invasive fish is one that people have carried outside its natural range, for farming, sport, the aquarium trade, mosquito control or by accident, and that spreads and harms native wildlife or livelihoods. Not every introduced fish becomes invasive, and some, such as tilapia and carps, are valued as food in the same places where they cause damage. Once established, invasive fish are very hard to remove.

Famous invasions

The Nile perch, put into Lake Victoria in the 1950s, helped drive many native cichlids to extinction. Indo-Pacific lionfish have spread through the western Atlantic and the Caribbean since the 1980s, eating young reef fish. Silver and bighead carps, brought to the United States to clean ponds, now crowd the Mississippi basin. The common carp makes up much of the fish in some Australian rivers. The sea lamprey devastated lake trout in North America's Great Lakes.

Invasive fish in India

India has introduced many fish for farming, and some have spread into the wild. The African catfish, called Thai magur, preys heavily on native fish, and its farming is banned. Tilapia now dominates catches in some reservoirs. Amazon sailfin catfish, released from aquariums, have spread through lakes and rivers from Kerala to West Bengal, damaging banks and nets. Scientists also warn that river-linking projects could spread fish between basins.

Famous invasive fish

Red lionfishInvasive across the western AtlanticNile perchTransformed Lake VictoriaAfrican sharptooth catfishThe African catfish, banned for farming in IndiaAmazon sailfin catfishAn aquarium escapee in Indian waters

Still to be written: Silver carp, Common carp, Northern snakehead, Round goby.

Further reading

GroupSharkRayCarpCatfishSalmonidHerringCodTunaPerch-likeCichlidReef fishEelFlatfishLivebearerAncientOther
WaterRivers and lakesEstuaries and mangrovesCoasts and shelvesCoral reefsOpen oceanDeep seaPolar and cold seasCaves and springsBetween sea and river
OrderBest knownA to ZOldest firstNewest firstBy size
🇪🇬 Egypt and 4 moreNile tilapia A hardy cichlid farmed globally for food.Cichlid · Rivers and lakes · 1758 🇳🇮 NicaraguaRed devil cichlid Large aggressive cichlid from Central American lakesCichlid · Rivers and lakes 🇲🇽 Mexico and 1 moreMayan cichlid A hardy cichlid from Mesoamerica with a distinctive tail spot.Cichlid · Rivers and lakes 🇮🇱 Israel and 1 moreBlue tilapia Hardy cichlid native to Africa and the Middle EastCichlid · Rivers and lakes Middle EastRedbelly tilapia A hardy cichlid from Africa and the Middle East.Cichlid · Rivers and lakes 🇲🇽 Mexico and 4 moreJack Dempsey Aggressive cichlid native to Central AmericaCichlid · Rivers and lakes

Photo credits on this page

The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

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