19th November – Selasphorus Saturday, Rufous or Allen’s?

Selasphorus hummingbird reports are now an annual occurrence in CT. Most of them are Rufous/Allen’s types, but  since the identification of Allen’s is almost impossible without banding them, proving one in CT is an uphill task. That many of the state’s selasphorus can be attributed specifically to Rufous is due to the banding efforts of Mark Szantyr and Jayne Amico. However, they can’t band them all, and so many reported birds are left as selasphorus sp. There are several records of Allen’s in the mid-atlantic states and New England (my only Allen’s was at Cape May in November 2000), so there is a good possibility that one will occur in CT sooner or later and each report should be checked out if, possible, to ensure we don’t overlook a potential Allen’s.

With this in mind, Nick Bonomo and I visited a bird coming to the feeder in nearby Guilford to see if we could slap a moniker on it, or at least try and get spread tail shots to help determine it’s identity – in Allen’s, the outer three tail feathers are narrower than in Rufous, so it was our mission to try and photograph the bird’s spread tail.

 Rufous Hummingbird, adult female, Guilford, Nov 2011. The obvious moult contrast in the primaries, with worn outer primaries and new inners, combined with some iridescent throat petals, made us age it as an adult. Juveniles would show more uniform wings with a spotted throat. The face was rather cold, lacking any rufous-wash, with a uniformly green back.

 Note prominent white forecollar, rufous flanks, fresh inner primaries and reduced rufous fringing to uppertail coverts

I confess to being confused with some of these birds, it’s a group I’m not that familiar with and so each time we get one of these it’s quite a learning experience, not only identifying them, but especially trying to age and sex them. Howell’s excellent Photographic Guide to Hummingbirds of North America was our reference.

We saw the bird well and photographed it from a distance, but unfortunately in the time we had, we were never able to get shots of the open tail, so it was destined to remain unidentifiable. According to Howell, one feature of adult female Allen’s is a propensity to have the uppertail coverts strongly fringed rufous. Our bird had some obvious rufous fringing , but without a baseline, our lack of experience left us asking “how much is enough?”. With Mark out of town, banding at present wasn’t an option, so it seems destined to fall into the selasphorus sp bin until Mike Moccio got  great shots of the spread tail which confirmed the bird to be a Rufous.

 Note in this fantastic shot, the relatively broad outer tail feathers compared with the narrower feathers that would be expected in an Allen’s. Also note the rufous on the uppertail coverts is limited to the fringes and is not that predominant. (Photo courtesy of Mike Moccio)

A cool bird, and as usual a challenging and educational experience! For instructional photos of an Allen’s banded in PA in 2009 see here: http://home.earthlink.net/~pomarine/id93.htmlLooking at these images the narrow pointed tail when seen from behind seem rather different from the broader, full tail of our bird. Also, in the flight shot note the obvious rufous uppertail coverts, perhaps two features to key into?

Here’s two shots of a (AHY female?) Rufous that was banded by Mark and Jane back in 2006.

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One Response to “19th November – Selasphorus Saturday, Rufous or Allen’s?”

  1. Harvey Says:

    R2 is what you need to see. Is it notched? If so it’s diagnostic for Rufous

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