White-crowned Sparrow- An Identification Difficulty

by Bryce W. Robinson

As a raptor enthusiast, I know the challenge juvenile and immature birds can present when grasping for identification. Sparrows are a vastly diverse group, with multiple similar looking species. This coupled with the variation of juvenile and immature plumage has presented quite the challenge in learning field identification for these birds. I am currently on location in south central Utah conducting winter raptor surveys, and have seen a fair number of sparrow species in this high desert landscape. I was able to catch this photograph that displays an immature bird that may stump the beginning birder.

This is an immature White-crowned Sparrow ( Zonotrichia leucophrys). For identification, note the buff cheek. Also, note the prominent wing bars and overall fresh appearance to the bird. I believe the White-crowned Sparrow has a complex alternate molt strategy, so this bird has gone through a pre-formative molt transitioning from juvenal plumage into this immature “first winter” formative plumage. In spring it will transition into breeding or alternate plumage when it undergoes a pre-alternate molt.

As I am currently conducting winter surveys for raptors, I have gathered quite a few wonderful pictures and stories I am excited to share. I am working on learning aging of Golden Eagles, and will soon share some photos of a few birds, and my ideas as to their age. I saw a Harlan’s Hawk today, and will return to the area tomorrow with hopes of photographing the striking creature. With luck, I will have something to share.

Till then, enjoy life.

B William

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