Fish are aquatic vertebrates that spend their entire lives in water. They do not need to come to the surface to breathe but instead use gills to extract oxygen from the water. Most fish are cold-blooded, so they cannot regulate their own body temperature, which instead varies depending on the surrounding environment.
There are approximately 28,000 different species of fish, which vary substantially in range, habitat, diet, behaviour, size, and colouration. They live in virtually all aquatic habitats on Earth.
Browse our A-Z archives to find out more about some fascinating fish species!
Fascinating facts about some of the world’s most amazing animals. From Aardvarks to Zebras our A-Z of the animal world is guaranteed to inspire. If your favourite animal’s not yet included, please let us know. Check out the Top 3 most loved animals! »
Most Atlantic Cod spawn between the months of January and April and females release up to five million eggs. Overfishing and specifically the harvesting of young fish before they have reproduced successfully is a serious threat to this fish.
Atlantic salmon are incredible fish that migrate thousands of miles in their lifetime from saltwater to freshwater habitats to spawn. Migrations are incredible to watch, with salmon leaping their way up streams and waterfalls!
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