Winter arrived December 21 on an unseasonably balmy day. Even with a warmer and drier projection for weather this season we will still undoubtedly experience our fair share of frigid temperatures. A 70 degree day in Patagonia can often be accompanied by a 30 degree night, for example.
Local wildlife species have an array of evolved behavioral and physiological responses to deal with such severe dips in the mercury. One of the most observable behavioral responses is the migration of birds. Of course, various species travel from northern climes to winter in the more amenable temperatures of our somewhat subtropical latitudes. Yet other species travel down from the higher elevations of our higher mountains to partake of the resources in lower elevation habitats. These are the altitudinal migrants that we’ll focus upon here.
Among the most elusive, yet spectacular of these winter wayfarers is the rightly famous elegant trogon. The male, in particular, is a show-stopper in terms of his gaudy plumage that may convert even the most reticent observer into an instant birdwatcher. Typically, the species nests in mid-elevational riparian forests with sycamore trees. Post-breeding, the majority of trogons head south of the border to wait out winter’s worst. A mere handful (usually males), however, are detected each winter in southeast Arizona—generally at lower elevations than during the breeding season.
My first encounter with a winter trogon was at our nature sanctuary near Patagonia Lake. It was January and I had just returned from Australia and its own array of striking avifauna. The day after arriving home I took a walk just below my house and heard the distinctive “bark” of an elegant trogon. Knowing their habitat preferences, I ignored the call, thinking that I must be “hearing things.” Soon, however, my eyes belied my doubt, as a male trogon came into view a mere 20 yards away! Making the sighting even more exciting was the fact that it was hunting in a mesquite/catclaw forest – miles from the nearest sycamore or stream. At Lake Patagonia several years ago, I watched a male trogon (the same one?) sup upon a large grasshopper that it had deftly nabbed, thereby explaining why some individuals linger in winter.
While winter trogon hunting is often a fruitless pursuit, other bird species regularly descend the mountains for the water, invertebrates, and warmth proffered by our lower habitats. I truly reckon cold weather has arrived when the ruby-crowned kinglets show up at our place. Normally denizens of higher coniferous or mixed forests, they shun winter’s worst by descending. Watching them frenetically forage in our woodlands, I’m always left aghast that they can actually find sufficient invertebrates to sustain their high-speed lifestyle.
All three species of North American bluebirds can be found at lower elevations in our area in winter. The mountain bluebird lives up to its moniker while breeding, though it readily comes down in small numbers to the edges of our woodlands and even grasslands in its quest for winter sustenance, as do the more common eastern and western bluebirds, which I often detect by flight calls. Within the lower elevations they are very much mobile – here one minute and gone the next. So too with cedar waxwings.
A bit more faithful in its choice of wintering locales is the red-shafted flicker – Arizona’s largest species of woodpecker. Normally, they breed at higher elevations and in denser forests, but during the colder months they grace us with their presence low down. Ants, their dietary mainstay, are much more frequently active in the valleys than in the mountains. Easy math! Coming down does, however, come with a price to pay at times. I have occasionally encountered ex-flickers in the form of a tell-tale, colorful pile of feathers with perhaps an odd body part thrown in as well. These individuals clearly fell prey to predatory birds. Cooper’s and sharp-shined hawks are certainly key suspects with perhaps an ambitious American kestrel thrown in at times. So too, surprisingly, are loggerhead shrikes, which I’ve witnessed attacking the much larger flickers – a sight to be seen.
Keep a look-out, too, this winter for other altitudinal migrants, such as: Hutton’s vireo, bridled titmouse, Cassin’s finch, Williamson’s and red-naped sapsuckers, and even such rarities as rufous-backed robin. Wait for the cold weather and let them come to you. Happy “hunting”!
Vincent Pinto and his wife, Claudia, run RAVENS-WAY WILD JOURNEYS LLC, their Nature Adventure & Conservation organization devoted to protecting and promoting the unique biodiversity of the Sky Islands region. RWWJ offers private birding & biodiversity tours. Visit: www.ravensnatureschool.org