No, a shark is a fish, and a whale is a mammal fish are cold-blooded, and mammals are warm-blooded. The best way to tell if you are looking at a whale or a shark is that the point of a shark's tail sticks up out of the water, but a whale's tail lies flat against the surface. Whales need air to breathe, which they do through blowholes on the top of their heads, but sharks do not need air to breathe, and have gills. Hammerhead sharks, great white sharks, and the Ganges shark are just three of the long list of endangered sharks.