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. 635 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
🇺🇸 United StatesCui-ui Endangered sucker fish native to Pyramid Lake in NevadaOther · Rivers and lakes 🇯🇵 Japan and 2 moreAyu sweetfish Small amphidromous fish prized for its sweet flesh in East Asia.Other · Rivers and lakes · 1846 🇺🇸 United StatesDelta smelt A tiny, endangered fish native to California's Sacramento-San Joaquin River Delta.Other · Rivers and lakes · 1963 🇳🇬 NigeriaHingemouth Small African fish with a unique proboscis-like mouthOther · Rivers and lakes 🇷🇺 RussiaComephorus Two species of pelagic sculpins endemic to Lake Baikal in Russia.Other · Rivers and lakes · 1800 🇯🇵 JapanRanchu A hooded goldfish breed from Japan with no dorsal fin and a rounded body.Other · Rivers and lakes 🇺🇸 United States and 1 moreEulachon A small anadromous smelt known for its high fat content and cultural importance in Pacific North America.Other · Rivers and lakes 🇩🇪 Germany and 4 moreEuropean smelt Small coastal fish with a cucumber scentOther · Rivers and lakes WorldBartail flathead A widespread marine flathead found across the Indo-Pacific.Other · Coasts and shelves · 1758 🇮🇳 India and 4 moreClimbing perch Amphibious freshwater fish capable of breathing air and moving on land.Other · Rivers and lakes · 1792 🇺🇸 United StatesAtlantic tarpon Large, acrobatic saltwater game fish of the Atlantic.Other · Coasts and shelves · 1847 🇮🇳 India and 4 moreStriped snakehead A large freshwater food fish native to South and Southeast Asia.Other · Rivers and lakes WorldPike Freshwater predatory fish genus with sharp teeth and torpedo shape.Other · Rivers and lakes 🇳🇿 New Zealand and 3 moreCommon galaxias A small migratory fish of the Southern Hemisphere.Other · Rivers and lakes 🇳🇿 New ZealandBanded kōkopu A striped New Zealand galaxiid that climbs waterfalls.Other · Rivers and lakes 🇳🇿 New ZealandNew Zealand grayling Extinct amphidromous fish endemic to New Zealand rivers and seas.Other · Rivers and lakes 🇮🇳 India and 4 moreGiant mudskipper Large amphibious goby found in Indo-Pacific mangroves.Other · Rivers and lakes 🇧🇩 Bangladesh and 3 moreIndian featherback Large silvery knifefish from South Asian riversOther · Rivers and lakes 🇺🇸 United States and 4 moreSmelt Small fish of the northern hemisphere known for spring runs and culinary traditions.Other · Rivers and lakes

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