Fish have more recognized species than any other vertebrate and their habitats range from the smallest freshwater streams to the deepest seafloor canyons. They grow from a fraction of an inch to 50 feet and live anywhere from the artic waters to the tropics. Fish skeletons can either be cartilaginous or bony, a category that includes the vast majority of fish.
Salmon are born in fresh water, migrate to the ocean as adults, and then return to fresh water to breed.
Science has never witnessed the spawning secrets of the American eel. Learn More
One of more than 70 species of surgeonfish, the blue tang inhabits coastal waters, coral reefs, and near-shore rocky areas. Learn More
Found across the globe in almost all tropical seas, the great barracuda is one of 20 barracuda species. Learn More
This fearsome predator attacks very few people. Fur seals are not so lucky, though! Learn more
The moray eel hides in reef holes and waits for its prey to swim within reach. Learn more
Sturgeon are believed to be one of the most ancient families of fish on the planet. Lean more
The planet's largest living fish, this docile giant lives in warm waters around the planet. Learn more
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