The second largest tern in North America (The Caspian Tern being the largest), Royal Terns are 12-21 inches long with a 42-44 inch wingspan. Adults have white crowns most of the year but a black cap is acquired briefly in spring and early summer (breeding season)

Royal Terns nest in dense colonies; these colonies can reach 10,000 birds along the Gulf Coast. The nests consist of a shallow scrape in the sand, lined with bits of grass.
They dive into the water from 40-50 fight to catch fish, and sometimes marine invertebrates (shrimp, squid, etc.). They can usually be seen on sandbars, beaches or mudflats along with other species of terns and seagulls.

The Royal Tern population is declining in California