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 flycatcher and Canada. This flycatcher builds a shallow cup nest high in a shrub or short tree. Females normally lay two or three eggs. The fork-tailed flycatcher is white below, gray above, and has a black cap. Males sometimes show a yellow crown stripe. Males also have an extremely long forked tail, of even greater length than that of their cousin, the scissor-tailed flycatcher. Females have a somewhat shorter tail, while it is significantly shorter in juveniles. Males are in length; females, , including tail. They weigh only , much less than closely related kingbirds, which are half the total length