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SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament

EveryFish

Invasive

Fish spread outside their home range where they cause harm. 22 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 Atlantic

Nile perchTransformed Lake Victoria

African sharptooth catfishThe African catfish, banned for farming in India

Amazon sailfin catfishAn aquarium escapee in Indian waters

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

Further reading

Photo credits on this page

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

Nile perch: Pavel Zuber, CC BY-SA 3.0, source
African sharptooth catfish: Unknown author, Public domain, source
Red lionfish: Photo by Jens Petersen , Edited by User:Olegiwit (cloned in part of fi, CC BY 2.5, source
Amazon sailfin catfish: Richwales at en.wikipedia, Public domain, source
Brown trout: Duane Raver, U.S. Fish and Wildlife Service, Public domain, source

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