Friday, October 30, 2009

Selasphorous Hummingbirds in New England

Rufous Hummingbird that's in NH

More rare hummingbirds are turning up in the Northeast at feeders. The latest is an Allen's Hummingbird (Selaphorous sasin) who has been coming to a feeder in Scituate, MA and has been banded and determined to be, most likely, an adult female. The bander is still checking with some experts before the ID is 100% sure. While the homeowner wishes to remain anonymous, the photos of the Allen's are posted on Mass. Audubon's South Shore Journal Blog, click here.

This would only be the second time an Allen's Hummingbird has been found in MA. I blogged (including my photos) about the Rufous Hummingbird (Selaphorous rufus) coming to a feeder in Hollis, NH. That was also banded and the bander felt they could not determine whether it was an immature female or male.

Both Rufous and Allen's Hummingbirds are rare in New England. Only a few, at most, Rufous are reported in New England each year; Allen's is more rare here. Rufous Hummingbirds breed in the Northwest and into Alaska; Allen's is mainly a West Coast Hummingbird.

Female and immature Allen's vs. Rufous Hummingbirds are notoriously hard to identify, even for banders, even when they are holding them in the hand. How hard??? Bear with me here while I walk you through some of the technicalities.

The bander's reference bible is the "Identificaton Guide to North American Birds" by Peter Pyle, a highly detailed reference for birds in the hand. Under Allen's Hummingbird it states "females and juv-HY/SY males from Rufous Hummingbird (with caution) by wg averages shorter by sex: r2 not notched to slightly notched by age/sex; outer rects narrower by age/sex."

Translation: Female and young male Allen's Hummingbirds are separated from Rufous Hummingbirds by slightly shorter wings and an r2 (which refers to the second tail feather from the central tail feather) that is not notched to slightly less notched than on Allen's. By notched, they are referring to a slight indentation or narrowing of the tip of the feather. The outer rects (rects refer to rectrices, which are tail feathers) are narrower on an Allen's vs. Rufous in these ages classes as well.

If your brain has wandered at this point to things like, who won last nights World Series game, what you're having for lunch or dinner, or why is Lillian bothering with this, that's understandable. This ID stuff IS VERY HARD, even for banders.

Meanwhile, the MA Allen's and the NH Rufous Hummingbirds are wearing new jewelry (bands), sipping sugar water from the feeders, and have no idea (or do they?) that they are off course for migration (according to us, maybe not them.)

2 comments:

Kat said...

I am not seeing anymore Ruby Throats at all. I am curious as to why you are still seeing hummingbirds that far north.

Lillian Stokes said...

Rubythroats have just about all left New England. These Rufous and Allen's Hummingbirds are more likely to show up here in fall, often after most Rubythroats have left. But they are rare hummers here and only a few show up each year.

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