San Joaquin Marsh, Irvine, CA, USA
The regal Caspian Tern is the largest tern in the world, easily recognized by its brilliant red fish-knife of a bill and deep, raspy call. Found all over the world, the Caspian favors both freshwater and saltwater environments. It feeds mostly on fish, captured in nimble aerial dives. On the nesting grounds, paired Caspian Terns perform splendid displays in the air, rising up to great heights in tandem. They migrate nocturnally, and in autumn their rolling calls are sometimes heard overhead during the night.
Caspian Terns prey mostly on fish, supplementing their diet with crustaceans such as crayfish and occasionally large insects. To locate prey, they fly above water, between 10 and 100 feet high, and scan the water with bill pointed downward. When they spot prey they dive rapidly, usually submerging the body in the process but sometimes snatching the prey from the water without diving in.