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EveryFish

Least concern

Widespread and not thought to be at risk. 286 fish on EveryFish so far.

Least Concern is the IUCN Red List category for species that have been assessed and are not close to qualifying as threatened. They are usually widespread and abundant. Many important food fish are in this category, including hilsa, rohu, skipjack tuna and Atlantic herring. Least Concern describes a species as a whole, worldwide; it does not mean that every local stock is healthy or well managed.

Common, not always safe

A fish can be Least Concern globally while particular populations are in trouble. Hilsa is widespread across the Bay of Bengal and its rivers, but its runs up the Ganges collapsed after the Farakka Barrage. Rohu and catla are abundant because they are farmed in huge numbers, while wild river stocks have declined. Herring stocks have crashed and recovered in different seas over the past century. Fisheries are managed stock by stock, so local assessments matter as much as the global category.

Back from the brink

Some fish have moved into Least Concern after recovering. The Atlantic bluefin tuna was listed as Endangered in 2011 after decades of overfishing; strict quotas set by the Atlantic tuna commission, ICCAT, and better enforcement let stocks recover, and in 2021 it was reassessed as Least Concern. Yellowfin tuna was moved from Near Threatened to Least Concern in the same update, though scientists warn that yellowfin in the Indian Ocean is still overfished.

Famous least concern fish

Further reading

🇧🇷 Brazil and 4 moreRedtail catfish A large South American catfish known for its red tail and popularity in the aquarium trade.Catfish · Rivers and lakes Sub-Saharan AfricaSynodontis A large African genus of spotted catfish known for squeaking sounds and belly-up swimming.Catfish · Rivers and lakes WorldHypostomus plecostomus A tropical armored catfish from South America, kept in aquariums for algae control.Catfish · Rivers and lakes · 1758 🇧🇷 Brazil and 4 moreAmazon sailfin catfish A large freshwater armored catfish from South America, often kept in aquariums and known as an invasive pest elsewhere.Catfish · Rivers and lakes Latin America and the CaribbeanBanjo catfish A South American family of scaleless, benthic catfish with a distinctive banjo-shaped body.Catfish · Rivers and lakes 🇧🇴 Bolivia and 4 moreRipsaw catfish Large thorny catfish native to South American rivers.Catfish · Rivers and lakes 🇧🇷 Brazil and 2 morePygmy corydoras A tiny armored catfish from South America kept in community aquariums.Catfish · Rivers and lakes · 1966 🇧🇷 Brazil and 1 moreAncistrus A genus of small, nocturnal freshwater catfish native to South America and Panama.Catfish · Rivers and lakes 🇮🇩 Indonesia and 4 moreWalking catfish A Southeast Asian air-breathing catfish known for moving across land and surviving out of water.Catfish · Rivers and lakes WorldCatfish A diverse order of ray-finned fish known for whisker-like barbels and lack of scales.Catfish · Rivers and lakes

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The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

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