Allen's hummingbird - a new record

Pennsylvania's first Allen's hummingbird (©Scott Weidensaul)

I was privileged to band Pennsylvania's first state record Allen's hummingbird today near Leola, Lancaster County - a healthy, beautiful adult female. This is the sixth fall/winter hummer I've banded this season, but the rest have been rufous hummingbirds - great birds, but now predictable every fall in the mid-Atlantic.

Allen's, though, was long overdue in Pennsylvania, since this native of coastal California and southwestern Oregon has been recorded a few times in neighboring states. But because the immatures and females are essentially indistinguishable in the field from rufous hummers, they are probably overlooked unless a bander is able to catch and identify the bird.

Last night, while I was speaking at the Lancaster Bird Club, one of the members mentioned a friend of hers who still had a hummingbird coming to a feeder. I asked her to have her friend call me, and this morning the phone rang. Two hours later, I was knocking at Debra Raudenbush's door. Half an hour after that, we had the hummingbird in my cage trap.

Like most of the hummingbirds I band, this one was very calm in the hand during the 10 or 15 minutes it took to band her. Once we were done, before I started shooting photos, I gave her a chance to drink from a feeder, and she lapped sugar water for two or three minutes - again, almost all hummingbirds will do this in the hand if given a chance.

Then Debra held the bird for a moment on the palm of her hand before it flew off.

(Both © Scott Weidensaul)

Allen's averages smaller than rufous, and the measurements for this bird, while on the upper end of the range for Allen's, were small for rufous. The clinchers, though, were the absence of any significant notching on R2 (the second tail feather from the center) and the very narrow R5, the outermost tail feather - 2.41mm in this bird, vs. 3.5-4mm for most of the rufous I catch.

Here's a comparison of tail feathers from three rufous I've caught in the past, and today's Allen's. (The birds regrow the feathers, which are taken as permanent voucher specimens, in a matter of weeks.) Note that while rufous may or may not have a notched R2, it always has a relatively wide R5. The Allen's had neither.

(©Scott Weidensaul)

How long will the hummer stay? It's hard to say. Debra says she's been coming to the feeder since September. Like many of the western hummingbirds, rufous and Allen's are remarkably cold-hardy, with the ability to drop into a deep, hibernation-like torpor at night to conserve energy. Although nighttime lows have been in the teens and 20s lately, that's not terribly challenging to these birds.

That said, most of them clear out of here by Christmas, and the exceptionally mild weather we had in November probably encouraged more of them to stick around later than usual. As of Tuesday, all five of the rufous hummers I'd banded this fall we still present in southeastern PA, although one had laid on heavy fat reserves, suggesting it was preparing to depart soon.

From banding and observation data, it appears most of the western hummingbirds coming through the East in fall and early winter eventually migrate to the Gulf coast region, where they overwinter. By banding this Allen's, she becomes part of a continental effort to track the evolution of a new migratory route and wintering area for this and several other species of hummingbirds.

On Halloween winds

I'm odd in a lot of ways – just ask my long-suffering wife – but one of the oddest, perhaps, is that I love being in the woods at night.

Humans are diurnal creatures; darkness leaves us semi-blind, feeling vulnerable. But I revel in being outdoors after dark, since the woods that are so familiar by day seem new, charged with possibility, every sound and smell magnified.

Yet even I feel a twinge of – well, call it unease, as the sun goes down. It only lasts for a few minutes, but when the forest teeters at the dusky edge of night, as the last daylight is seeping away and the shadows are spilling out from beneath the hemlocks and below the fallen logs, something very deep and very primal in me squirms. Nighttime was the time of lions and hyenas, leopards and other big predators that saw early hominids as prey, and our genes have never forgotten it.

But once the darkness settles, that antediluvian twinge vanishes, and I'm free to enjoy the nocturnal forest.

It's something I do a lot of at this time of the year. Halloween is the midpoint in an eight-week research season that rolls around every fall, when I (along with my crew of 18 licensed banders and 85 volunteers) explore the nocturnal migration of the northern saw-whet owl, the smallest raptor in the East, and one of the least-known.

A saw-whet is the size of a man's fist, weighing about 90 grams (roughly the same as a robin), and cute as a button – unless you're a deer mouse or a red-backed vole, of course, in which case, this pint-sized hunter is your worst nightmare. They breed in forested regions across the northern United States and Canada, south in the southern Appalachians, and in the western mountains from Alaska deep into Mexico.

Until the 1960s, they were not considered to be regular migrants, and as recently as the early 1990s, few people suspected they migrate in large numbers down the ridges of the Appalachians, where I live. My friends Eric and Melonie Atkinson first started studying them in the Pennsylvania ridge country in 1996, and I began banding them the following year.

For the past 11 years, I've overseen a major saw-whet study through the Ned Smith Center for Nature and Art in Millersburg, PA, which tries to shed more light on this mysterious bird. Each October and November, at three sites in central Pennsylvania, my crew and I lure saw-whets out of the sky with a recording of the male's territorial call, a mechanical toot, and into our line of long, high mist nets, which hold them harmlessly.

We band the owls with a lightweight, numbered metal band supplied by the federal Bird Banding Lab, take a quick series of measurements, and send them on their way. (A few also receive a radio transmitter the size of a pencil easer, so we can track their movements; a few other sacrifice a few small feathers, so we can analyze their DNA.)

Last night was a perfect night for saw-whet migration. A cold front had roared through Saturday, and all day Sunday, the chill wind blew and the sky was full of puffy gray cumulus clouds. Then at sunset the wind died to flat calm, and the thermometer began sinking toward frost.

My crew of five volunteers and I opened the nets at sunset, and by the time we wrapped things up at 1:30 a.m., we had netted 36 saw-whets – our second-best night since we started doing this work more than a decade ago. One of the owls was already banded, an adult female originally caught in 2005 in Massachusetts; most years we catch several dozen such "foreign" owls, and an equal number of ours are reported by other banders.

Through such work do we learn where and when birds migrate, how long they live, whether they come back to the same breeding and wintering locations, and much more.

But it also allows me to connect with a part of the natural world about which most people are entirely ignorant – the wild, nocturnal part, when legions of little owls flood south across the continent, borne on Halloween winds.