Double Crested Cormorant "are opportunistic, generalist feeders" (Wires, Cuthbert, Dale, & Joshi, 2001). They feed on slow moving fish species that range from 3 centimeters to 40 centimeters. These birds forage in shallow water and seem to be strict diurnal in the way they eat. They are quick to respond to areas with high fish concentration and flock where the fish can easily be caught.
The Double Crested Cormorant breeds in cold climatic conditions and has been living in Alaska for a long time (Wires, Cuthbert, Dale, & Joshi, 2001, p. 36). According to Siegel-Causey & Savinetskii (1991), the remains of the bird have been found on Amchitka Island dating back over 2000 years. These remains suggest that the there were plenty of the species in the central Aleutian Islands and climate changes have reduced their population in Alaska.
Great Blue Herons
Great Blue Herons are prey generalists, although they forage for fish. They catch their prey as they walk along the shores of water bodies such as oceans, lakes, marshes and...
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