Examination of five coastal species of sea birds on Long Island, New York, revealed 18 cases of subcutaneous emphysema among over 11,000 chicks handled over a 5 year period. The condition may result from a variety of causes, but trauma to young birds from territorial adults is believed to play an important role. The condition is often benign, but when severe may interfere with both cryptic posture and escape. It should be distinguished from generalized edema, a condition which might occur in the same populations. Treatment is simple and usually successful.