Parasitic Jaeger (Stercorarius parasiticus), San Carlos Lake, Gila County

This Parasitic Jaeger was found by Tommy DeBardeleben on 12 September 2018 and was photographed by Babs Buck on 16 September and by Tommy DeBardeleben on 19 September 2018

Casual in Arizona, if accepted by the ABC this would represent the 19th state record and the eighth away from the lower Colorado River. This bird was originally seen on the Gila County side of the lake, and on September 18th it was found in Pinal County in addition to Gila County by Mark Stevenson, Molly Pollock, and Dave Stejskal.

Identification of juvenile jaegers is complex. Parasitic is the only species to have such a relatively small-headed appearance and muted barring, especially on the upper and undertail coverts. The bill is intermediate in size between Long-tailed and Pomarine. The underwing pattern of Parasitic Jaeger is variable; this individual shows a hint of a "double flash" caused by pale bases to the underprimary coverts similar to that shown by Pomarine Jaeger. Parasitic Jaegers can vary in this characteristic from a two-toned pattern like Pomarine to a strongly barred pattern like Long-tailed. Most importantly, on this bird the two pointed central tail feathers extend moderately beyond the rest of the tail, whereas this extension is rounded and very short in Pomarine and longer in Long-tailed.

16 September 2018, photo by Babs Buck

19 September 2018, photo by Tommy DeBardeleben

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