Ocean fishes come in all shapes, sizes, colors and live in drastically different depths and temperatures. Despite this diversity, the United Nations Food and Agriculture Organization reported in 2016 that 89.5% of fish stocks are fully fished or over fished. All fish are cold-blooded animals that live in the water. They have backbones, fins, and gills.
Fish come in more varieties than any other group of vertebrate animals. There are 32,000 different species of fish. There are three major types or classes of fish including jawless, cartilaginous, and bony fish. An example of a jawless fish is the lamprey eel. Sharks are cartilaginous fish and the blue marlin is a bony fish.
Fish vary in all sorts of colors and sizes. Fish can be as large 40 ft long to 1/2 inch long. There are some animals that live in the water and we may think of as fish, but really aren't classified by scientists as fish. These include whales, dolphins, octopus, and jellyfish.