The Common Tern, scientific name Sterna hirundo, is a seabird belonging to the family Laridae. It is a medium-sized tern measuring about 14-16 inches in length and weighing around 2-4 ounces. The Common Tern has a slender, pointed bill, long wings, and a forked tail. It also has a distinct black cap on its head and a white body, with gray wings and back.
One of the most distinguishing field marks of the Common Tern is its call, a sharp, piercing “kee-yah.” During breeding season, their bills turn bright orange-red, and they develop a black collar around their neck. In contrast, during the non-breeding season, their bills are black, and they lose their black collar.
Common Terns are migratory birds, breeding in the northern hemisphere and migrating to the southern hemisphere during winter. They breed along coastal areas and on islands, forming large colonies. During breeding season, they feed on small fish and invertebrates, which they catch by plunge-diving into the water from mid-air.
During migration, Common Terns can be seen flying over large bodies of water, often in large flocks. They follow coastal and inland routes, stopping along the way to rest and feed. Some Common Terns travel as far south as the southern tip of South America, while others stay closer to their breeding grounds in North America.
The Common Tern is a widespread and abundant species, with a stable population trend. However, they are vulnerable to habitat loss, disturbance, and predation, particularly during the breeding season. Conservation efforts, such as the protection of breeding habitats and the reduction of human disturbance, can help ensure the survival of this beautiful seabird.