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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
EveryFish

Rivers and lakes

Fresh water: rivers, streams, lakes and ponds. 178 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
🇨🇦 Canada and 1 moreLake chub A small cold-water minnow native to Canada and the northern US.Carp · Rivers and lakes 🇦🇹 Austria and 4 moreEuropean mudminnow Small freshwater fish from Central and Eastern EuropeOther · Rivers and lakes 🇺🇸 United States and 1 moreGreen sturgeon A large anadromous fish native to the northern Pacific Ocean.Shark · Coasts and shelves 🇺🇸 United States and 2 moreBluegill A common North American sunfish known for its blue gill covers and popularity with anglers.Perch-like · Rivers and lakes · 1854 East AsiaAmur pike A spotted freshwater pike native to east Asia.Other · Rivers and lakes 🇷🇺 Russia and 3 moreBurbot A coldwater freshwater fish with a chin whisker, native to the Northern Hemisphere.Other · Rivers and lakes · 1758 🇷🇺 Russia and 1 moreRuffe A small, aggressive freshwater fish native to Eurasia that has become a major invasive pest in North America.Perch-like · Rivers and lakes · 1758 🇧🇷 Brazil and 4 moreArapaima Giant air-breathing freshwater fish of the AmazonOther · Rivers and lakes · 1822 🇺🇸 United States and 2 moreRock bass A small, red-eyed freshwater sunfish native to North America.Perch-like · Rivers and lakes WorldLabeobarbus A genus of mid-sized ray-finned fish widely distributed in eastern and southern Africa.Carp · Rivers and lakes 🇺🇸 United StatesCrappie Two species of North American freshwater sunfish prized by anglers for sport and food.Perch-like · Rivers and lakes 🇵🇰 Pakistan and 1 moreGolden mahseer Large cyprinid fish from Himalayan riversCarp · Rivers and lakes 🇺🇸 United States and 1 moreSpotted gar A small North American freshwater fish with a long snout and spotted scales.Ancient · Rivers and lakes · 1860 🇨🇳 China and 3 moreAsian swamp eel A freshwater, air-breathing fish native to Asia and introduced elsewhere.Eel · Rivers and lakes 🇺🇸 United States and 1 morePacific lamprey An anadromous parasitic jawless fish found along the Pacific Rim.Ancient · Rivers and lakes · 1872 🇯🇵 JapanNigorobuna Wild carp from Lake Biwa used for fermented sushi.Carp · Rivers and lakes 🇺🇸 United StatesWhite bass A silver-striped freshwater fish native to North American rivers and lakes.Other · Rivers and lakes 🇺🇸 United States and 1 moreAlewife A small North American herring that migrates between sea and rivers.Herring · Coasts and shelves WorldDanio A genus of small striped freshwater fish from Asia kept in aquaria.Other · Rivers and lakes · 1822 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 🇦🇷 Argentina and 4 moreArgentinian silverside A large, adaptable silverside native to South America.Other · Rivers and lakes WorldKillifish Small egg-laying fish known for hardiness and short lifespansLivebearer · Rivers and lakes WorldArowana Freshwater bony fish with a toothed bone in the mouth and air-breathing ability.Ancient · Rivers and lakes · 1831 🇺🇸 United StatesLeast killifish A tiny North American fish that gives birth to live young and measures just two centimetres long.Livebearer · Rivers and lakes 🇺🇸 United States and 4 moreMosquitofish Small North American fish introduced globally for mosquito control.Livebearer · Rivers and lakes 🇺🇸 United StatesEastern mosquitofish A small livebearing fish native to the eastern US, now invasive in many regions.Livebearer · Rivers and lakes · 1859 🇯🇵 JapanJapanese rice fish Small freshwater fish native to Japan and a key model organism.Other · Rivers and lakes 🇧🇷 Brazil and 1 moreLargescale four-eyes Surface-dwelling fish with split eyes for dual vision.Livebearer · Rivers and lakes · 1758 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 🇲🇽 MexicoButterfly splitfin A critically endangered livebearing fish from Mexico.Livebearer · Rivers and lakes · 1971 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 🇨🇳 ChinaTelescope goldfish Fancy goldfish breed with large protruding eyesCarp · Rivers and lakes 🇯🇵 JapanRanchu A hooded goldfish breed from Japan with no dorsal fin and a rounded body.Other · Rivers and lakes WorldTetra Common name for small freshwater characiform fishes popular in aquaria.Livebearer · Rivers and lakes 🇧🇷 BrazilBlack arowana A South American freshwater fish known for its dark colour and jumping hunting style.Other · Rivers and lakes 🇮🇩 Indonesia and 4 moreAsian arowana Large freshwater fish from Southeast Asia known for its metallic scales and cultural significance.Ancient · Rivers and lakes · 1840 🇵🇦 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 🇺🇸 United StatesSouthern cavefish A blind cavefish from the eastern United States.Other · Rivers and lakes · 1859 Fire eel 🇹🇭 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 🇸🇳 Senegal and 3 moreSenegal bichir Ancient African fish that breathes air and walks on landAncient · Rivers and lakes
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