Herring Gull
This gull is similar to the California gull, but has white eyes and pink legs and feet. It tends to be a scavenger, following boats and frequenting dumps. It spends the winter in the Bay area, nesting in northern Canada and Alaska.

Mew Gull
The gull is so-named because its call sounds like a low mewing. This is a small gull, about 16 inches long, with a white head, a short yellow bill, white spots on black wingtips and yellow legs and feet. It nests in Alaska and northern Canada, but spends the winter in the Bay area.

Caspian Tern
The largest North American tern, the stocky Caspian tern is about the size of a California gull, approximately 21 inches from head to tail. The adult has a brilliant orange bill, a black cap which fades in winter, and black legs and feet. The body is light gray above and white below. It is common on the Bay in the spring and summer.

Elegant Tern
The aptly named Elegant tern visits the central and south Bay between July and October. It is slightly smaller than the Caspian tern, with a long thin, orange bill, and black cap, legs and feet. Its tail is much more deeply forked than that of the Caspian gull.

Forster's Tern
This tern looks like a smaller version of the Caspian except that its bill is thinner and orange-red as are its legs and feet. Its tail is deeply forked. The Caspian gull, with a length of 14 inches, is the most common tern on the Bay during the spring nesting season and the summer.

California Least Tern
With a length of only 9 inches, the California least tern is the smallest North Americana tern. It resembles the Forster's tern except that its bill, legs and feet are orange-yellow instead of orange-red and its wing beat is quicker. It has black wing tips during the breeding season. The species was listed as endangered in 1970 but today is making a slow comeback. Approximately 100 pairs of terns have been found nesting in colonies at the Alameda Naval Air Station and the Oakland International Airport, where they are now protected.