What is another name for a common seagull?

Actually, there are 45 species of gulls.

Seagull is an incorrect term used to describe all gulls. Some common gulls are the herring, black backed, laughing, Franklin's, ring billed, Thayer's, California, Sabine's, Iceland, Black headed, Bonaparte's, little, glaucous, ivory, Ross', and black legged kittiwake.