You may think you know what a fish is, but this group of animals actually has a very specific definition. To be a fish, the animal must have specific physical features:
Scientists classify fish into two major groups: the jawless (Agnatha) fishes and the jawed (Gnathastomata) fishes.
Native Fish in Parks
National parks contain about 60% of all native freshwater fish species that occur within the United States. Many unique, native fish make their homes in national parks.
Last updated: February 13, 2018