News
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

Coral reefs

The warm, clear water of coral reefs. 0 fish on EveryFish so far.

Coral reefs grow in warm, clear, shallow tropical seas, built by colonies of tiny coral animals that lay down limestone. They cover a very small part of the sea floor but hold roughly a quarter of all marine fish species, often thousands in one region. The Coral Triangle of South-East Asia is the richest, and India's reefs lie around the Andaman and Nicobar Islands, Lakshadweep and in the Gulfs of Mannar and Kutch.

Crowded and colourful

Reef fish divide food and space finely. Grazers such as parrotfish and surgeonfish crop algae; butterflyfish pick at coral; groupers, snappers and reef sharks hunt along the edges; cleaner wrasses pick parasites off larger fish; and clownfish shelter among anemones. Most reef fish are territorial or stay close to one patch of reef, and many feed by day while others, such as cardinalfish and squirrelfish, come out at night.

Reefs under heat

Marine heatwaves cause corals to bleach and die, and the fish that depend on them decline. Mass bleaching has become more frequent, with the fourth global event confirmed in 2024. Overfishing, blast and cyanide fishing, pollution and coastal building add to the stress. Some reef fish carry ciguatera toxins, and a few, such as lionfish and stonefish, are venomous. Well-protected reserves often hold more and larger fish.

Still to be written: Ocellaris clownfish, Humphead wrasse, Green humphead parrotfish, Moorish idol, Bluestreak cleaner wrasse, Whitetip reef shark, Red lionfish, Synanceia verrucosa.

Further reading

The weekly digest

Every Monday: the fish of the day, new pages on EveryFish, and the conferences and anniversaries of the week ahead.