Monday, July 11, 2011

California Gull

During our June visit to Olympia, Washington, my family took me to the ocean.  Birding on the seashore  is normally rewarding.  Our expedition was an exception--we listed only a few birds.  One of these birds was this California Gull.

California Gulls breed in scattered locations from the Prairie Provinces of Canada south through the northern arid West and northwest Great Plains.  These gulls winter along the Pacific coasts of the United States and Mexico, often fairly far out at sea.  Off Washington, first year birds are often encountered further from the shore than are adults.  One hypothesis for this distribution is that the young are forced further out by competition with adults.   Nonbreeding individuals, like the bird in my photograph, are often found along these coasts in the summer.

The California Gull in this photograph is somewhat oddly plumaged. This species takes three years to reach adult plumage.  First-year birds have dusky brown bodies, blue-gray legs, and pale bills with black tips.  Third-year birds are generally white with gray backs, black wings, and yellow legs.  Second-year birds are variable in plumage and leg color.  This California Gull appears to be a second-cycle bird that has retained the gray legs but is molting into adult plumage.  Note the black band and red spot on the bill, both field marks of a third-cycle individual.  Other adult characters include the red eye-ring and dark eye.  A photograph of a very similarly plumaged California Gull with gray legs is found in Howell and Dunn (2007).  Identification using many other field guides, however, would be difficult.  I think I have mentioned in previous posts that gull identification can be vexing.

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