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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. 403 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

Further reading

🇺🇸 United States and 2 moreAmerican gizzard shad A silvery freshwater forage fish with a muscular gizzard.Herring · Rivers and lakes 🇳🇬 NigeriaHingemouth Small African fish with a unique proboscis-like mouthOther · Rivers and lakes 🇺🇸 United StatesAmerican paddlefish Ancient freshwater fish with a sensory snout and filter-feeding habits.Ancient · Rivers and lakes · 1792 🇷🇺 Russia and 1 moreBaikal black grayling A Siberian freshwater salmonid found in Lake Baikal and surrounding river systems.Salmonid · Rivers and lakes 🇹🇭 Thailand and 3 moreSiamese tigerfish A critically endangered freshwater perch from Indochina.Perch-like · Rivers and lakes · 1998 🇨🇺 CubaCuban gar Large tropical freshwater predator native to western Cuba.Other · 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 🇷🇺 RussiaCaspian roach A brackish water fish from the Caspian Sea region, widely consumed as a dried snack.Carp · Estuaries and mangroves WorldSnakehead Elongated freshwater predators with air-breathing organs found in Asia and Africa.Other · Rivers and lakes 🇧🇷 Brazil and 1 moreArapaima Large freshwater fish from the Amazon basin known for its size and air-breathing ability.Ancient · Rivers and lakes 🇸🇳 Senegal and 3 moreWest African lungfish Air-breathing freshwater fish from AfricaAncient · Rivers and lakes 🇷🇺 Russia and 4 moreSiberian sturgeon Large freshwater sturgeon native to Siberian riversAncient · 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 🇹🇭 Thailand and 2 moreSiamese mud carp Freshwater cyprinid native to Mekong and Chao Phraya riversCarp · Rivers and lakes 🇨🇳 China and 1 moreMandarin fish Freshwater predatory perch native to East AsiaPerch-like · Rivers and lakes · 1855 🇧🇷 Brazil and 4 moreHoplias aimara A large freshwater predator from South America known for its size and mercury accumulation.Other · Rivers and lakes · 1846 🇦🇴 Angola and 3 moreMarbled lungfish African lungfish with the largest known animal genome, found in East and Central Africa.Ancient · Rivers and lakes 🇨🇳 ChinaChinese paddlefish A giant freshwater predator from China that is now extinct.Ancient · Rivers and lakes · 1862 🇨🇦 Canada and 1 moreGoldeye A silver freshwater fish known for its smoked culinary form.Other · Rivers and lakes 🇨🇦 Canada and 1 moreLake chub A small cold-water minnow native to Canada and the northern US.Carp · Rivers and lakes 🇺🇸 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 🇷🇺 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 🇺🇸 United StatesCrappie Two species of North American freshwater sunfish prized by anglers for sport and food.Perch-like · Rivers and lakes 🇧🇮 Burundi and 3 moreGiant cichlid The largest living cichlid species, native to Lake Tanganyika in Africa.Cichlid · Rivers and lakes · 1899 🇨🇳 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 🇦🇷 Argentina and 4 moreArgentinian silverside A large, adaptable silverside native to South America.Other · Rivers and lakes 🇺🇸 United States and 4 moreMosquitofish Small North American fish introduced globally for mosquito control.Livebearer · Rivers and lakes 🇧🇷 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 🇰🇭 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 🇧🇷 BrazilBlack arowana A South American freshwater fish known for its dark colour and jumping hunting style.Other · Rivers and lakes 🇧🇷 Brazil and 1 moreSilver arowana Large South American freshwater predator with bone tongue.Other · Rivers and lakes Karonga tilapia 🇲🇼 Malawi and 2 moreKaronga tilapia Endangered cichlid from Lake Malawi and the Shire River.Cichlid · Rivers and lakes WorldCichlid Diverse freshwater fish family known for parental care and rapid evolution.Cichlid · Rivers and lakes · 1835 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 OceaniaBanded archerfish A silvery fish that spits water jets to catch prey.Perch-like · Estuaries and mangroves · 1767 🇨🇳 China and 4 moreThree spot gourami Hardy freshwater fish native to Southeast Asia with distinct side spots.Other · Rivers and lakes WorldDamselfish Small marine fish known for aggressive territorial behaviour and reef farming.Reef fish · Coasts and shelves WorldMoray eel A global family of elongated marine eels known for their powerful jaws and patterned skin.Eel · Coasts and shelves

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