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. 191 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 AmazonGolden 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

Still to be written: Mekong giant catfish.

Further reading

GroupSharkRayCarpCatfishSalmonidHerringCodTunaPerch-likeCichlidReef fishEelFlatfishLivebearerAncientOther
UseFood fishFarmedAquarium fishSport fishingCulture and faithVenomous or dangerousInvasiveScience and research
OrderBest knownA to ZOldest firstNewest firstBy size
🇸🇳 Senegal and 3 moreSenegal bichir Ancient African fish that breathes air and walks on landAncient · Rivers and lakes Sub-Saharan AfricaMbu pufferfish Large carnivorous freshwater puffer from the Congo River.Other · Rivers and lakes South AsiaGreen spotted puffer Small brackish water pufferfish with a tiny genomeOther · Rivers and lakes 🇰🇭 Cambodia and 1 moreFigure 8 puffer A small brackish water pufferfish with distinctive eye-like markings.Other · Rivers and lakes OceaniaBanded archerfish A silvery fish that spits water jets to catch prey.Perch-like · Estuaries and mangroves · 1767 Sub-Saharan AfricaFreshwater butterflyfish Surface-dwelling African fish that glides above water.Other · Rivers and lakes 🇮🇩 IndonesiaBoeseman's rainbowfish A colourful freshwater fish from West Papua lakes.Other · Rivers and lakes 🇦🇺 Australia and 1 moreThreadfin rainbowfish Small freshwater fish with long, elegant fins from Australia and New Guinea.Other · Rivers and lakes · 1974 🇵🇬 Papua New GuineaForktail blue-eye A small freshwater fish from Papua New Guinea rainforests.Livebearer · Rivers and lakes 🇮🇩 IndonesiaDwarf rainbowfish Small, iridescent freshwater fish from West Papua.Other · Rivers and lakes Bluefin notho 🇲🇿 MozambiqueBluefin notho A small annual killifish from Mozambique kept in aquaria.Livebearer · Rivers and lakes · 1926 🇬🇦 GabonLyretail panchax Small colourful freshwater killifish from GabonLivebearer · Rivers and lakes 🇮🇩 IndonesiaCelebes rainbowfish A small, transparent silverside from Sulawesi streams.Other · Rivers and lakes 🇬🇳 Guinea and 2 moreClown killi Small West African freshwater fish with ringed patternsLivebearer · Rivers and lakes · 1915 🇳🇬 Nigeria and 1 moreBlue lyretail A colourful West African killifish kept in home aquariums.Livebearer · Rivers and lakes · 1911 🇨🇩 Democratic Republic of the CongoCongo tetra A colourful African freshwater fish kept in home aquaria for its bright scales and feathery tail.Other · Rivers and lakes · 1899 🇧🇷 Brazil and 2 moreBlack tetra Small freshwater characin with dark vertical barsOther · Rivers and lakes 🇧🇷 BrazilRummy-nose tetra Small Amazonian characin with a red head and striped tail.Other · Rivers and lakes · 1924 🇺🇸 United States and 1 moreLongfin smelt Small anadromous fish of the North Pacific coastOther · Rivers and lakes 🇧🇷 BrazilEmber tetra Tiny orange freshwater fish from BrazilOther · Rivers and lakes · 1987 Bleeding heart tetra WorldBleeding heart tetra Small Amazonian fish with a red flank spotOther · Rivers and lakes · 1943 Latin America and the CaribbeanPenguinfish Small striped characin from South American riversOther · Rivers and lakes 🇧🇷 BrazilLemon tetra Small yellow freshwater fish from the Amazon basin.Other · Rivers and lakes 🇧🇷 Brazil and 1 moreX-ray tetra Small translucent South American freshwater fish popular in home aquariums.Other · Rivers and lakes · 1894 🇨🇴 ColombiaEmperor tetra A small freshwater fish from Colombia, prized in the aquarium trade for its striking colours and distinct sexual dimorphOther · Rivers and lakes 🇧🇷 Brazil and 4 moreMarbled hatchetfish A small South American freshwater fish kept in aquariums for its unique shape and surface-dwelling habits.Other · Rivers and lakes · 1864 🇻🇪 VenezuelaDiamond tetra Small Venezuelan freshwater fish with violet finsOther · Rivers and lakes · 1920 🇧🇴 Bolivia and 3 moreCommon hatchetfish Small freshwater fish from South AmericaOther · Rivers and lakes WorldSplash tetra Small South American fish that lays eggs on leaves above waterOther · Rivers and lakes 🇨🇳 China and 4 moreThree spot gourami Hardy freshwater fish native to Southeast Asia with distinct side spots.Other · Rivers and lakes 🇰🇭 Cambodia and 3 moreMoonlight gourami A small, silvery labyrinth fish native to Southeast Asian rivers and swamps.Other · Rivers and lakes Southeast AsiaPygmy gourami A tiny freshwater fish from Southeast Asia known for its iridescent colours and ability to make sounds.Other · Rivers and lakes Chocolate gourami 🇲🇾 MalaysiaChocolate gourami Small maternal mouthbrooding fish from Southeast Asian peat swampsOther · Rivers and lakes 🇨🇳 China and 1 moreParadise fish Aggressive freshwater gourami from East AsiaOther · Rivers and lakes WorldPeters's elephantnose fish A West African freshwater fish that navigates using weak electric pulses.Other · Rivers and lakes WorldDamselfish Small marine fish known for aggressive territorial behaviour and reef farming.Reef fish · Coasts and shelves 🇺🇸 United States and 1 moreRazorback sucker Endangered river fish with a distinctive back ridgeOther · Rivers and lakes WorldMoray eel A global family of elongated marine eels known for their powerful jaws and patterned skin.Eel · Coasts and shelves WorldCardinalfishes Small, colourful reef fish known for male mouthbrooding.Reef fish · Coasts and shelves 🇲🇽 Mexico and 2 moreMexican molly Small livebearing fish from Mexico and Central America.Livebearer · Rivers and lakes 🇺🇸 United States and 1 moreSailfin molly Small livebearing fish with a large dorsal fin in males.Livebearer · Rivers and lakes · 1821 🇲🇽 Mexico and 1 moreSouthern platyfish Small live-bearing freshwater fish from Central AmericaLivebearer · Rivers and lakes 🇲🇽 MexicoVariable platyfish Small livebearing fish from Mexico popular in home aquariumsLivebearer · Rivers and lakes 🇧🇷 Brazil and 2 moreCardinal tetra Small freshwater fish with a bright red belly and iridescent blue stripe.Other · Rivers and lakes · 1956 🇲🇽 Mexico and 1 moreGreen swordtail A hardy live-bearing fish popular in home aquariums.Livebearer · Rivers and lakes · 1848 🇧🇷 BrazilBlack neon tetra Small freshwater characin with white and black stripes, popular in the aquarium trade.Other · Rivers and lakes 🇺🇸 United StatesDevils Hole pupfish A tiny fish found only in one cavern in Nevada.Other · Rivers and lakes · 1930
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