The red-legged kittiwake breeds in colonies on sheer cliffs (4). They arrive at the breeding colonies in April and depart in September, dispersing to the south over the open ocean over the north-east Pacific and as far east as the Gulf of Alaska (4). A single brood, consisting of two eggs, is produced each breeding season. The eggs are incubated for 23 to 32 days, and the chicks fledge at 38 to 48 days of age (3).
Feeds on small fish (such as lampfish), marine invertebrates, including squid, and on carrion (4) (3).