Тёмная крачка Onychoprion fuscatus

This tropical seabird is distinctive among terns with its jet-black back, black cap, and neat white forehead. Immature birds are entirely dark blackish with white spots on wings and a white undertail. Most similar to Bridled Tern, but darker black back, dark undersides of flight feathers, and narrower white edges on tail. Sooty Tern is found in warm tropical waters worldwide. It breeds in colonies on sandy islands, but otherwise usually stays far offshore, and is rarely seen near land except when blown off course by a hurricane.