[Mystery bird] House Finch, Carpodacus mexicanus, photographed in a backyard in Houston, Texas. [I will identify this bird for you in 48 hours]
Image: Joseph Kennedy, 28 March 2010 [larger view].
Nikon D200, Kowa 883 telescope with TSN-PZ camera eyepiece 1/640s f/8.0 at 1000.0mm iso400.
Please name at least one field mark that supports your identification.
This species has an interesting feature that provides insight into its life history — can you tell me what that feature is and what it reveals about this particular bird?
Male House Finches grow plumage that varies in color from pale yellow to brilliant red. The red is a pigment color that comes from the bird’s diet. Thus, the redder the bird, the better its diet has been since the last time it moulted. When a male bird’s color varies away from red, it is due to one of two reasons: either improper diet or physiological stress.
Interestingly, after House Finches were introduced into Hawaii, nearly all of the males are yellow in color, as is the above pictured bird. This is quite surprising as Hawaii has a lot of vegetation that could serve as food for these birds. Though the population of House Finches seems to be doing well, their discolored plumage seems to suggest otherwise.