News
SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA 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 ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliamentSpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It AgainOceanEye to eye with Britain's hidden sharks at SharkAdemy - OceanographicRiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at allOceanShedd Aquarium Sends Shark Eggs to Bolster Wild PopulationsSpeciesA 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 ConservationOceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray AreaSpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow ReductionsFisheriesAdams River Salmon Run in Thompson-NicolaIndiaHilsa production dropped 26% in five years, fisheries minister tells parliament
EveryFish

Rivers and lakes

Fresh water: rivers, streams, lakes and ponds. 454 fish on EveryFish so far.

Rivers, lakes, streams and ponds hold less than one per cent of the Earth's water, yet about half of all known fish species live in them. Fresh water is broken into separate basins, and fish that cannot cross between them evolve apart, which is why each river system and lake has its own species. The Amazon, Congo, Mekong and Ganges basins and the great lakes of Africa are the richest.

Life in fresh water

A freshwater fish is saltier inside than the water around it, so it must pump salt in through its gills and pass a lot of dilute urine. Freshwater habitats range from torrential Himalayan streams, where loaches cling to rocks, to warm, still swamps where air-breathing snakeheads, catfish and gouramis thrive. Many river fish time their spawning to floods: the Indian major carps spawn in the monsoon floodwaters, and Mekong fish move into flooded forests.

The most threatened fish

Freshwater fish are declining faster than sea fish. A 2021 report by conservation groups found that about a third of freshwater fish species are threatened with extinction and that 80 had already been declared extinct. Dams block migrations, water is drawn off for farms and cities, pollution and sand mining degrade rivers, and introduced species such as tilapia and African catfish compete with native fish. In India, the rivers of the Western Ghats and the North-East hold many endemic fish at risk.

Famous rivers and lakes fish

RohuA river carp of the Indian subcontinentArapaimaAn air-breathing giant of the AmazonMekong giant catfishOne of the largest freshwater fishGolden mahseerThe golden mahseer of Himalayan riversNile perchA huge predator of African lakesRed-bellied piranhaA schooling fish of South American riversZebrafishA small fish of South Asian streams

Further reading

GroupSharkRayCarpCatfishSalmonidHerringCodTunaPerch-likeCichlidReef fishEelFlatfishLivebearerAncientOther
UseFood fishFarmedAquarium fishSport fishingCulture and faithVenomous or dangerousInvasiveScience and research
OrderBest knownA to ZOldest firstNewest firstBy size
🇧🇷 Brazil and 4 moreRedtail catfish A large South American catfish known for its red tail and popularity in the aquarium trade.Catfish · Rivers and lakes 🇨🇦 Canada and 1 moreBigmouth buffalo A long-lived North American freshwater fish known for its terminal mouth and exceptional lifespan.Catfish · Rivers and lakes 🇺🇸 United StatesBrown bullhead A hardy North American catfish known for surviving poor water conditions.Catfish · Rivers and lakes · 1819 🇺🇸 United States and 1 moreYellow bullhead A medium-sized North American catfish known for its bright yellow belly and scavenging habits.Catfish · Rivers and lakes · 1819 🇺🇸 United StatesBlack bullhead A small, hardy North American catfish that tolerates poor water conditions and feeds at night.Catfish · Rivers and lakes 🇦🇺 AustraliaEel-tailed catfish Venomous freshwater catfish native to eastern AustraliaCatfish · Rivers and lakes 🇺🇸 United StatesBlue catfish A large North American catfish known for its size and invasive spread in eastern US waters.Catfish · Rivers and lakes 🇺🇸 United States and 2 moreFlathead catfish A large North American freshwater predator known for its broad head and carnivorous diet.Catfish · Rivers and lakes 🇹🇭 Thailand and 2 moreGiant pangasius A large freshwater catfish from Southeast Asia, now critically endangered due to overfishing and habitat loss.Catfish · Rivers and lakes · 1931 🇺🇦 Ukraine and 4 moreWels catfish A large freshwater catfish native to Europe and Western Asia, known for its size and bottom-feeding habits.Catfish · Rivers and lakes · 1758 🇹🇭 Thailand and 4 moreMekong giant catfish A massive freshwater fish native to the Mekong basin, now critically endangered.Catfish · Rivers and lakes 🇧🇷 BrazilPiraíba A massive Amazonian catfish known for its long barbels and role as an apex predator.Catfish · Rivers and lakes 🇺🇸 United States and 2 moreChannel catfish A widespread North American freshwater catfish, prized for food and sport.Catfish · Rivers and lakes · 1819 WorldGiant catfish Large estuarine catfish found across the Indo-Pacific.Catfish · Estuaries and mangroves · 1837

Photo credits on this page

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

The weekly digest

Every Monday: the fish of the day, new pages on EveryFish, and the conferences and anniversaries of the week ahead.