The most widespread cormorant in North America, the double-crested cormorant (Phalacrocorax auritus) can be found in parts of our area (Northeastern California) throughout the year. Yet, in my experience, this cormorant is quite shy and usually flies off before I and my 200 mm lens can get close enough to photograph it. Last week I spent a half hour slowly working my way toward this pair of double-crested cormorants on Baum Lake (Shasta County CA) and finally got close enough for some fair pictures.
Double-crested cormorant adults (the sexes are similar) are black with black legs and a hooked bill that is blackish above and paler with spots below. They have a yellow or orange gular (throat) pouch and bare yellow or orange supraloral (between eye and bill) skin. Except during the breeding season the double-crested cormorant’s eyes are brownish while during the breeding season the eyes are aquamarine. The inside of the mouth is also blue. The cormorant shows its blue mouth while courting and to defend its territory. (I would love to get close enough to see the blue mouth!) The common name for the double-crested cormorant derives from the small double crest of black or white feathers seen during the breeding period. Immatures are brownish overall and palest on the neck and breast.
Living near bodies of fresh or marine water, double-crested cormorants survive mainly on fish but will take a few insects, amphibians or crustaceans, which they capture by diving. When a double-crested cormorant catches a crayfish it will hold the crayfish in its bill and hammer it on the top of the water to shake off the legs before tossing the crayfish in the air and catching it headfirst and swallowing it whole.
This large water bird has less preen oil than many other waterfowl and thus it gets wet. Double-crested cormorants can often be seen on rocks, tree limbs, docks and other perches where they stand with their wings outspread to dry off after fishing. Double-crested cormorants ride low in the water when swimming and often their long, snaky head is all that is visible.
Double-crested cormorants winter mostly along the North American coasts during the winter and a population of them migrates to the continental interior during the summer. We are fortunate to have this cormorant as a year-long resident.