There are many varieties of seabird (too many to discuss here!). Here are characteristics of seabirds: |
• Seabirds are found on all continents and islands around the world. |
• Seabirds can be highly pelagic, coastal, or partly terrestrial. |
• Most species nest in colonies (dozens to millions of birds) |
• Seabirds live longer, breed later, and have fewer young. |
• Many species undertaking long annual migrations, crossing the equator or even circumnavigating the Earth. |
• Seabirds feed both at the ocean's surface,below it, and even on each other. |
• All seabirds share feed in saltwater (some may feed in both sea and terrestrial sources). |
• Wing morphology and body shape depends the niche a species or family has evolved.
-- Longer wings and low wing loading are typical of more pelagic species,
-- Diving species have shorter wings.
-- Seabirds like albatross and pelicans use dynamic soaring to take advantage of wind deflected by waves to provides lift. |
• Seabirds also almost always have webbed feet. |
• Salt glands in their nasal cavities are used to excrete the salt they ingest by drinking and feeding. |
• Birds appear in the Mesozoic Era, but modern seabirds proliferated in the Paleogene (after the K/T extinction). |