The third of the medium-sized New England nesting terns (along with Common and Roseate) is the world-traveling Arctic Tern. Weighing in at roughly 4 ounces, these birds are believed to annually migrate longer distances than any other creature on earth. Yearly estimates are around 25,000 miles.
In Maine, Arctic Terns nest in colonies on a small number of islands. Breeding birds have a long, forked tail, a deep-red bill, and (as the photo shows) a white stripe between their black cap and gray body. Their calls are somewhat similar to Common Terns. (Listen to the following embedded sample.)
Arctic Terns may be more numerous than Roseate Terns, but they are nonetheless listed as threatened by the state of Maine, due in large part to the fact that most of them nest on just a handful of offshore islands. A few pairs nested on Stratton Island this summer.