Swallow-tailed gull and hunting over the open oceans, and migrating eastward to the coasts of Ecuador and Peru. The swallow-tailed gull is unique among the gulls in feeding exclusively nocturnally, mostly on fish and squid which rise to the surface at night to feed on plankton. It leaves the colony as a flock at dusk, with a great deal of screaming and display. Calls and displays are quite different from other gulls, most resembling the vocalisations of the black-legged kittiwake and Sabine's gull. The loudest and most commonly heard call is an alarm referred to as "rattle-and-whistle", a gurgling scream made with
Fork-tailed storm petrel been conducted to discern the two subspecies. The range of the fork-tailed storm petrel is estimated to cover 22,400,000 km with over 6,000,000 individuals occurring globally, making it the second most widespread and abundant storm petrel. During the breeding season, the fork-tailed storm petrel form dense colonies on islands throughout northern California, Oregon, Washington, British Columbia, Alaska, and northeast Asia off the Kamchatka Peninsula. Most of their abundance is concentrated in Alaska, notably in the Bering Sea near the Aleutian Islands. Their southernmost colony is on Little River Rock in Humboldt County, with a population of 200 individuals. Their nesting