William Borden, age 12, of Galveston, Texas, for his question:

HOW LARGE CAN A JAEGER BE?

Jaeger is the common name for a number of large sea birds. Jaegers are powerful fliers that look somewhat like large gulls. They average from 16 to 23 inches in length, depending on the species.

The birds are usually grayish brown or blackish above and white or light gray below. They have slightly hooked beaks, long, narrow wings, two long tail feathers and webbed toes with long, sharp talons.

Jaegers attack slower and weaker sea birds such as terns and gulls in midair, forcing them to give up whatever goods they have in their beaks or even forcing them to disgorge what they have swallowed. They feed on small rodents, fish and the eggs and young of other birds.

Three species winter in North America, where they are commonly known as sea hawks, robber gulls and teasers. The pomarine Jaeger is common in the winter off the coast of New England; the parasitic Jaeger is found along both coasts in winter; and the long tailed Jaeger winters off the Atlantic coast. They nest in Arctic regions on cliffs or plains.