Double-crested Cormorant

One of those birds that seems particularly inappropriately named if you're used to seeing it in Sonoma County. Double-crested Cormorant has crests on either side of its head only when in breeding plumage (photo below). Normally the birds we see are in non-breeding plumage, like the bird above, although the bird shown above is puffing out its throat, giving it a somewhat uncharacteristic profile. What is characteristic in the above photo is the orange-yellow around the bird's mouth; the hooked bill; the blue-black color (note that the patterning on the back is usually less visible; in most lights Double-crested Cormorant appears fairly uniformly blackish); the short, brush-like tail; and the fact that the bird is perched in a tree. Double-crested Cormorant may be found at the coast, but also along lakes and rivers inland. Juveniles (see below) are brownish and pale at the breast and throat (sometimes light brown, sometimes almost cream-colored there).

Large groups sometimes roost together in trees. Birds may be seen holding out their wings to dry (especially after rain), looking rather like something out of a Charles Addams cartoon--although the cartoon birds are presumably vultures. Known to nest at the mouth of the Russian River. Generally silent, but makes grunting noises in breeding colonies or when startled. Colonies may be of nests either in trees or on the ground (often on rocks, although not clinging to precipitous cliff faces, which is typical of the other two species of cormorant found in the county), but, according to The Birder's Handbook, these two styles of nesting are never mixed.

Three species of cormorant are normally present in Sonoma County--Double-crested Cormorant, Brandt's Cormorant (Phalacrocorax penicillatus), and Pelagic Cormorant (Phalacrocorax pelagicus); only Double-crested cormorant is likely to be found inland and perched in a tree. Brandt's and Pelagic Cormorant are exclusively coastal species. The three species can be found together fairly reliably at the mouth of the Russian River. The National Geographic Field Guide to the Birds of North America notes that the crests that appear in breeding plumage are usually white or near-white in birds in the Western states but black and less obvious in birds found in the East. Double-crested Cormorant flies with a characteristic kink in the neck less conspicuous in both Brandt's and Pelagic, which fly with their necks held straight. Brandt's Cormorant has a pale beige to white throat patch that acquires a blue segment in breeding plumage (photo below). Pelagic Cormorant, meanwhile, is the smallest and most slender of the three species and has a notably thin bill without the bulge and hook at the end that both Double-crested Cormorant and Brandt's Cormorant show. The entire head of Pelagic Cormorant looks small when seen beside Brandt's. Pelagic Cormorant also develops white patches at the flanks in breeding plumage that make it very easy to spot, especially in flight. In breeding plumage, Pelagic Cormorant will have red at the base of the bill.

Swimming cormorants are often confused with loons at a distance because they swim similarly low in the water and typically with their heads held up, which may suggest Red-throated Loon (Gavia stellata) in particular.