Thursday, October 1, 2015

Trip report: Laramie hotspots

This past Saturday Shawn Billerman led a group of Auduboners to several Laramie parks in search of migrating passerines. Along the Greenbelt we found many Spizella sparrows--mostly Chipping but with a few Clay-coloreds--and foraging flocks of Wilson's, Orange-crowned, and Yellow-rumped warblers. "Stink Lake" in LaBonte Park hosted several species of dabbling ducks and a lone California Gull. The links below take you to our complete checklists.

Greenbelt - Optimist Park
Greenbelt - Flint St
LaBonte Park
Greenhill Cemetery

However, the most unusual bird of the day--dare I say, best bird of the day?--was a sapsucker at Greenhill Cemetery. The bird seems to be a Red-naped x Yellow-bellied Sapsucker hybrid. I have included Shawn's description of the bird and one of his photos below; see our eBird checklist linked above for more photos.

"Presumed hybrid individual that showed intermediate characteristics between Red-naped and Yellow-bellied Sapsucker. This bird had us leaning toward Yellow-bellied, due to the black border around the red throat and overall lack of a red nape, but these traits were imperfect for Yellow-bellied. The black border around the red throat was very narrow and irregular, and had some red extending over it when the bird was in certain positions. The nape was not clean white, and had a pinkish wash that suggests introgression with Red-naped. The markings on the back are also not consistent with pure Yellow-bellied, being in two rows that are too narrow for typical Yellow-bellied, and possibly too wide for pure Red-naped. This hybrid combination is not well understood, in part due to the strong similarity between the two species. These two species are known to hybridize in the Rocky Mountains in southwestern Alberta. Presumed hybrids have been documented in eastern Colorado, and likely pass through this region regularly but are overlooked due to the difficulty of identification."

Presumed Red-naped x Yellow-bellied Sapsucker. Photo © Shawn Billerman.

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