Rivers and lakes
Fresh water: rivers, streams, lakes and ponds. 397 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
ZebrafishA small fish of South Asian streamsFurther reading
WorldRasbora
A diverse genus of small freshwater fish native to South and Southeast Asia.Carp · Rivers and lakes · 1822
🇲🇽 Mexico and 3 moreXiphophorus
A genus of small livebearing fish native to Mexico and Central America, known for aquarium use and genetic research.Livebearer · Rivers and lakes
🇦🇺 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
🇲🇽 MexicoButterfly splitfin
A critically endangered livebearing fish from Mexico.Livebearer · Rivers and lakes · 1971
🇨🇳 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
🇨🇳 ChinaTelescope goldfish
Fancy goldfish breed with large protruding eyesCarp · Rivers and lakes
🇵🇪 PeruAgassiz's dwarf cichlid
Small Amazonian cichlid with colourful males.Cichlid · Rivers and lakes
WorldCichlid
Diverse freshwater fish family known for parental care and rapid evolution.Cichlid · Rivers and lakes · 1835
🇹🇭 Thailand and 4 moreFire eel
Large spiny eel with red markings from Southeast AsiaOther · Rivers and lakes
🇹🇭 Thailand and 3 morePeacock eel
A small freshwater spiny eel from Southeast Asia.Eel · 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
🇵🇬 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
🇲🇿 MozambiqueBluefin notho
A small annual killifish from Mozambique kept in aquaria.Livebearer · Rivers and lakes · 1926
🇮🇩 IndonesiaCelebes rainbowfish
A small, transparent silverside from Sulawesi streams.Other · Rivers and lakes
🇳🇬 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
Photo credits on this page
The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.
- Rohu: Wiki Farazi, CC0, source
- Nile perch: Pavel Zuber, CC BY-SA 3.0, source
- Bichir: 5snake5, CC0, source
- Arapaima: This illustration was made by Citron You must credit this : Citron / C, CC BY-SA 3.0, source
- Zebrafish: Roundish, CC0, source
- Golden mahseer: Khalid Mahmood, CC BY-SA 4.0, source
- Rasbora: Captain R C Beavan, Public domain, source
- Xiphophorus: Marrabbio2, CC BY-SA 3.0, source
- Rainbowfish: Eileen Kortright ( Roan Art ), CC BY 2.5, source
- Killifish: TinoStrauss, CC BY-SA 3.0, source
- Arowana: User:Qwertzy2, CC BY-SA 3.0, source
- Least killifish: Brian Gratwicke, CC BY 2.0, source
- Japanese rice fish: NOZO, CC BY 3.0, source
- Largescale four-eyes: Michael Gäbler, CC BY 3.0, source
- Red-bellied piranha: Gregory Moine, CC BY 2.0, source
- Red-bellied Pacu: Omnitarian, CC BY-SA 3.0, source
- Butterfly splitfin: Przemysław Malkowski, CC BY-SA 3.0, source
- Headstander: Brian Gratwicke, CC BY 2.0, source
- Butterfly loach: Lerdsuwa, CC BY-SA 3.0, source
- Gyrinocheilus aymonieri: Pseudogastromyzon, Public domain, source
- Telescope goldfish: Lawrencekhoo, CC BY-SA 4.0, source
- Ranchu: Lerdsuwa, CC BY-SA 4.0, source
- Tetra: Holger Krisp, CC BY 3.0, source
- Black arowana: Dương Vinh Hoàng, CC BY-SA 4.0, source
- Asian arowana: Marcel Burkhard, CC BY-SA 3.0, source
- Glass knifefish: User:Haplochromis, CC BY-SA 3.0, source
- Agassiz's dwarf cichlid: Sychriscar, CC BY-SA 3.0, source
- Cichlid: mendel, CC BY-SA 1.0, source
- Peacock eel: Unknown author, Public domain, source
- Mbu pufferfish: Liné1, CC BY-SA 3.0, source
- Green spotted puffer: Starseed, CC BY-SA 3.0 de, source
- Figure 8 puffer: ColdmachineUK, CC BY 2.5, source
- Banded archerfish: Chrumps, CC BY-SA 3.0, source
- Freshwater butterflyfish: Toniher, CC BY-SA 3.0, source
- Threadfin rainbowfish: Unknown author, CC BY-SA 2.5, source
- Forktail blue-eye: Dirk Godlinski, CC BY-SA 3.0, source
- Dwarf rainbowfish: Raimond Spekking, CC BY-SA 4.0, source
- Lyretail panchax: Alexander Prokoshev, CC BY-SA 3.0, source
- Celebes rainbowfish: Shigella dysenteriae at English Wikipedia, CC BY-SA 3.0, source
- Clown killi: Oscar le poisson, CC BY-SA 3.0, source
- Blue lyretail: Violaine2, France, CC BY-SA 3.0, source
- Congo tetra: André Karwath aka Aka, CC BY-SA 2.5, source
- Black tetra: emptyvi, CC BY-SA 3.0, source
- Rummy-nose tetra: Gavinevans, CC BY-SA 3.0, source
- Ember tetra: Pascal Wolterman, CC BY-SA 3.0, source
- Penguinfish: Juan R. Lascorz, CC BY-SA 3.0, source
- Lemon tetra: Waugsberg, CC BY 2.5, source
- Mekong giant catfish: KKPCW, CC BY-SA 4.0, source