I was without binoculars, cameras, even a scope when I found a Long-tailed Jaeger on 06/20/2020 in central Wyoming. Talk about being in a situation where a swear word or two may be appropriate. Luckily, I was able to get my camera before the bird left. This appears to be the first photo-documented record for the state of Wyoming.
This is likely a '2nd summer' or '2nd cycle' individual. If you do not know what those terms mean, the plumage indicates this bird was born in 2018. It has undergone an incomplete prealternate molt, which is known to occur in birds this age. The 2nd prealternate molt in Long-tailed Jaegers gives them an adult-like appearance, however they still retain some feathers indicating their youth. Long-tailed Jaegers typically begin to breed around this age, and it is possible this bird failed to breed in the Arctic and has started its migration away from the breeding grounds.
Note, a major ID key for this species is the white shafts of the outer two primaries. Size, bill, and limited dark cap also play a role in identification.
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I observed the bird feeding on a variety of arthropods, which this species is quite capable of due to its smaller size and more slender stature. I will share photos of the insects it was eating in the following days. Unfortunately, the bird is not chaseable for local birders.