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EveryFish

Estuaries and mangroves

Where rivers meet the sea: estuaries, backwaters and mangroves. 29 fish on EveryFish so far.

Brackish water is the mix of fresh and salt water found in estuaries, lagoons, backwaters and mangrove creeks, where rivers meet the sea. Its saltiness rises and falls with the tides and the seasons, so only fish that can cope with change live there all the time. These waters are rich in food from the land and the sea, and they act as nurseries for many fish that later live on coasts and reefs.

Fish that handle change

Brackish-water fish are euryhaline: they can adjust the salt balance of their bodies as the water changes. Mullets, milkfish, scats, barramundi and the pearlspot live in India's backwaters and lagoons, such as Vembanad in Kerala and Chilika in Odisha. Mudskippers climb out onto mangrove roots at low tide, breathing through their wet skin. Archerfish shoot down insects from overhanging leaves. Bull sharks swim from the sea into estuaries and far up rivers.

Farms and pressures

Coastal ponds that take in tidal water are used to farm fish and shrimp: the bheris of West Bengal, the pokkali fields of Kerala and the milkfish ponds of the Philippines and Indonesia. Estuaries are also where ports, cities and industries crowd, and many are polluted or reclaimed. Clearing mangroves for shrimp farms has removed nurseries for wild fish across tropical Asia, and dams upstream cut the fresh water that keeps estuaries brackish.

Famous estuaries and mangroves fish

MilkfishFarmed in brackish ponds across Asia

Still to be written: Barramundi, Green chromide, Giant mudskipper, Scatophagus argus, Flathead grey mullet, Banded archerfish, Bull shark.

Further reading

GroupSharkRayCarpCatfishSalmonidHerringCodTunaPerch-likeCichlidReef fishEelFlatfishLivebearerAncientOther
UseFood fishFarmedAquarium fishSport fishingCulture and faithVenomous or dangerousInvasiveScience and research
OrderBest knownA to ZOldest firstNewest firstBy size
🇪🇬 Egypt and 4 moreNile tilapia A hardy cichlid farmed globally for food.Cichlid · Rivers and lakes · 1758 WorldNile perch Large freshwater predator native to Africa, now invasive in many lakes.Other · Rivers and lakes 🇿🇦 South Africa and 4 moreAfrican sharptooth catfish Large airbreathing catfish farmed across Africa and AsiaCatfish · Rivers and lakes 🇵🇭 Philippines and 4 moreMilkfish The sole living species of the family Chanidae, found across the Indo-Pacific.Other · Coasts and shelves 🇺🇸 United States and 1 moreAtlantic sturgeon A large anadromous fish native to the western Atlantic Ocean and its river systems.Ancient · Rivers and lakes 🇺🇸 United States and 1 moreShortnose sturgeon A small, endangered North American sturgeon with a short snout.Ancient · Rivers and lakes · 1818 🇷🇺 Russia and 2 moreKaluga A massive semi-anadromous sturgeon from the Amur River basin hunted for caviar.Ancient · Rivers and lakes · 1872 🇺🇸 United States and 2 moreLongnose gar A primitive ray-finned fish with a long snout and armored scales found in North America.Other · Rivers and lakes · 1758 🇲🇽 Mexico and 2 moreTropical gar A small freshwater predator from Central America known for its armored scales and air-breathing ability.Ancient · Rivers and lakes 🇺🇸 United States and 2 moreGar Ancient armored fish with lung-like swim bladders found in North American waters.Ancient · Rivers and lakes · 1758 🇧🇯 Benin and 4 moreSaddled bichir A large African freshwater fish with primitive lungs and multiple dorsal finlets.Ancient · Rivers and lakes · 1845 🇧🇷 Brazil and 4 moreMawsonia Extinct giant coelacanth from the Jurassic and Cretaceous periods.Ancient · Rivers and lakes · 1907 🇺🇸 United States and 1 moreDesert pupfish Small desert fish that survives extreme heat and saltOther · Rivers and lakes · 1853 🇺🇸 United StatesDelta smelt A tiny, endangered fish native to California's Sacramento-San Joaquin River Delta.Other · Rivers and lakes · 1963 🇨🇺 CubaCuban gar Large tropical freshwater predator native to western Cuba.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 🇺🇸 United States and 2 morePupfish Small killifish known for surviving in extreme isolated waters.Livebearer · Rivers and lakes 🇷🇺 Russia and 4 moreSabre carp A silvery surface feeder from Eastern Europe and Asia.Carp · Rivers and lakes WorldFeatherbacks and knifefishes Freshwater bony-tongued fishes with long anal finsOther · Rivers and lakes WorldThree-spined stickleback Small northern fish known for rapid evolution and complex breeding.Other · Rivers and lakes EuropeEuropean bullhead Small freshwater sculpin found in European rivers and streams.Other · Rivers and lakes 🇸🇳 Senegal and 3 moreSenegal bichir Ancient African fish that breathes air and walks on landAncient · Rivers and lakes 🇨🇳 ChinaChinese paddlefish A giant freshwater predator from China that is now extinct.Ancient · Rivers and lakes · 1862 🇷🇺 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 🇺🇸 United States and 1 moreSpotted gar A small North American freshwater fish with a long snout and spotted scales.Ancient · Rivers and lakes · 1860 🇲🇽 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 🇦🇷 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

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