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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
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Rivers and lakes

Fresh water: rivers, streams, lakes and ponds. 386 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 StatesDevils Hole pupfish A tiny fish found only in one cavern in Nevada.Other · Rivers and lakes · 1930 🇺🇸 United States and 2 moreFreshwater drum A hardy North American freshwater fish known for its grunting sound.Other · Rivers and lakes 🇨🇦 CanadaChain pickerel Freshwater predator with a dark chain pattern on green sides.Other · Rivers and lakes · 1818 WorldLoach Small bottom-dwelling freshwater fish found across Eurasia and Africa.Other · Rivers and lakes · 1758 🇮🇩 IndonesiaChili rasbora Tiny red and black fish from Borneo swamps kept in aquariums.Other · Rivers and lakes 🇲🇲 Myanmar and 2 morePearl danio Small tropical freshwater fish with an iridescent sheen.Other · Rivers and lakes 🇮🇩 IndonesiaKuhli loach A slender, nocturnal freshwater fish from Southeast Asia popular in aquariums.Other · Rivers and lakes · 1846 🇮🇩 IndonesiaClown loach Striped tropical freshwater fish from IndonesiaOther · Rivers and lakes · 1852 🇬🇧 United Kingdom and 4 moreStone loach A small European freshwater fish that hides under gravel and hunts at night.Other · Rivers and lakes 🇫🇷 France and 1 moreEuropean bitterling Small freshwater fish that breeds inside musselsOther · Rivers and lakes · 1782 🇺🇸 United StatesBonytail chub Endangered freshwater fish from the Colorado River Basin known for its thin tail.Other · Rivers and lakes 🇪🇬 Egypt and 3 morePebbly fish A silver characin from African rivers and lakes.Other · Rivers and lakes Sub-Saharan AfricaFahaka pufferfish Large tropical freshwater puffer from African river basins.Other · Rivers and lakes 🇹🇩 Chad and 2 moreAfrican brown knifefish Nocturnal freshwater fish with a knife-shaped body and fused fins.Other · Rivers and lakes
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