News
RiversEl Niño seen disrupting fish migration patternsSpeciesScientists 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-NicolaRiversEl Niño seen disrupting fish migration patternsSpeciesScientists 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-Nicola
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
WorldSpotted scat A spotted, square-bodied fish from Indo-Pacific estuaries.Other · Rivers and lakes · 1766 🇮🇳 IndiaZebra loach A small, striped freshwater fish from India's Western Ghats, kept in aquariums and eaten locally.Other · Rivers and lakes · 1920 WorldWeather loach Small freshwater fish active before stormsOther · Rivers and lakes 🇵🇾 Paraguay and 3 moreBuenos Aires tetra Hardy silver freshwater fish with red fins and a black tail mark.Other · Rivers and lakes · 1907 🇹🇭 Thailand and 2 morePearl gourami Small Southeast Asian fish with a pearly patternOther · Rivers and lakes · 1852 Southeast AsiaBumblebee goby Small striped freshwater and brackish gobies from AsiaOther · Rivers and lakes 🇮🇩 IndonesiaRed rainbowfish A bright red freshwater fish from Lake Sentani, Indonesia.Other · Rivers and lakes · 1907 Southeast AsiaKissing gourami A Southeast Asian freshwater fish known for its unique mouth-to-mouth sparring behaviour.Other · Rivers and lakes WorldSilver dollar Round, silver tropical fish related to piranhas, popular in aquariums.Other · Rivers and lakes 🇨🇳 China and 4 moreCelestial Eye goldfish Fancy goldfish with upward-facing telescope eyesOther · Rivers and lakes 🇧🇼 Botswana and 1 moreAfrican tigerfish Predatory freshwater fish known for sharp teeth and leaping hunting behaviour.Other · Rivers and lakes · 1861 WorldLeopard bush fish A freshwater labyrinth fish from the Congo River basin kept in home aquariums.Other · Rivers and lakes 🇧🇷 Brazil and 3 moreTambaqui A large freshwater fish from South America known for its heavy body and seed-eating habits.Other · Rivers and lakes 🇺🇸 United States and 1 moreMexican tetra A freshwater characin with surface and blind cave forms, studied for evolutionary biology.Other · Rivers and lakes 🇧🇷 Brazil and 4 moreWolf fish A predatory freshwater ray-finned fish found across Central and South America.Other · Rivers and lakes 🇦🇴 Angola and 3 moreAtlantic mudskipper Semi-aquatic goby that walks on mudflats in West Africa.Other · Rivers and lakes · 1766 🇨🇮 Ivory Coast and 4 moreAfrican pike characin West African freshwater predator with a pike-like shapeOther · Rivers and lakes · 1794 🇳🇬 NigeriaHingemouth Small African fish with a unique proboscis-like mouthOther · Rivers and lakes 🇧🇷 BrazilBanded leporinus A striped freshwater fish from the Amazon kept in home tanks and occasionally caught by anglers.Other · Rivers and lakes WorldFeatherbacks and knifefishes Freshwater bony-tongued fishes with long anal finsOther · Rivers and lakes Southeast AsiaGiant snakehead A large freshwater predator from Southeast Asia known for air breathing and invasive potential.Other · Rivers and lakes 🇧🇷 Brazil and 4 moreArapaima Giant air-breathing freshwater fish of the AmazonOther · Rivers and lakes · 1822 WorldDanio A genus of small striped freshwater fish from Asia kept in aquaria.Other · Rivers and lakes · 1822 🇦🇺 Australia and 2 moreRainbowfish Small colourful freshwater fish from Australia and New GuineaOther · Rivers and lakes · 1894 🇯🇵 JapanJapanese rice fish Small freshwater fish native to Japan and a key model organism.Other · Rivers and lakes Serpae tetra 🇧🇷 Brazil and 4 moreSerpae tetra Small red freshwater fish from South AmericaOther · Rivers and lakes · 1882 🇧🇷 Brazil and 4 moreRed-bellied piranha A widespread South American freshwater fish known for its omnivorous diet and shoaling behavior.Other · Rivers and lakes 🇧🇷 Brazil and 1 moreRed-bellied Pacu A large South American freshwater fish related to piranhas, farmed for food and kept in aquariums.Other · Rivers and lakes WorldHeadstander South American freshwater fish known for swimming with their heads pointed downwards.Other · Rivers and lakes 🇨🇳 ChinaButterfly loach A small, flat freshwater loach from fast Chinese streams.Other · Rivers and lakes 🇰🇭 Cambodia and 4 moreGyrinocheilus aymonieri A Southeast Asian freshwater fish known for its suction-like mouth and role in the aquarium trade.Other · Rivers and lakes 🇯🇵 JapanRanchu A hooded goldfish breed from Japan with no dorsal fin and a rounded body.Other · Rivers and lakes 🇧🇷 BrazilBlack arowana A South American freshwater fish known for its dark colour and jumping hunting style.Other · Rivers and lakes 🇵🇦 Panama and 1 moreGlass knifefish Translucent electric fish from South American riversOther · Rivers and lakes 🇧🇷 Brazil and 1 moreSilver arowana Large South American freshwater predator with bone tongue.Other · Rivers and lakes Fire eel 🇹🇭 Thailand and 4 moreFire eel Large spiny eel with red markings from Southeast AsiaOther · 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 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 🇮🇩 IndonesiaDwarf rainbowfish Small, iridescent freshwater fish from West Papua.Other · Rivers and lakes 🇮🇩 IndonesiaCelebes rainbowfish A small, transparent silverside from Sulawesi streams.Other · Rivers and lakes 🇨🇩 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 🇧🇷 BrazilEmber tetra Tiny orange freshwater fish from BrazilOther · Rivers and lakes · 1987
More fish

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.