Wayne R. Petersen
DAVID LARSON
This issue’s mystery species is obviously a seabird; however, there is not a lot of detail to offer a clue as to what species it is. Unlike some of the previous At a Glance photographs, there are few advantages to viewing the image on the Bird Observer website because the bird is primarily dark above with only hints that it is at least partially white below. Many seabirds are dark above and light below because countershading of this type is frequent among many seabird species. The uniformity of coloration on the upper wing surface is potentially useful.
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