also: かいちょう
seabird; sea bird
General term for birds that live primarily in marine environments.
この島には多くの海鳥が生息している。
Many seabirds inhabit this island.
海鳥の観察が趣味です。
Seabird watching is my hobby.
Standard kanji form; reading かいちょう is more common in news and formal contexts.
Alternate reading, somewhat less common but still used.
Compound of 海 (sea) and 鳥 (bird).