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Tucson Audubon Society (This article first appeared in the Vermilion Flycatcher, newsletter of the Tucson Audubon Society, February 2005.) Sometimes all it takes to become a better birder is to spend a few hours inside—as seven Tucson Audubon Society members discovered when they joined Rick Wright for a tour of the bird collections at the University of Arizona. Ornithologist and collections manager Tom Huels provided an extensive tour of the collections in his care, showing us everything from 100-year-old nests and skeletons to study skins of such colorful exotics as motmots and toucans. As we followed him from case to case, Tom interwove anecdote, history, and ornithology to explain the often surprising links between old-fashioned natural history, cutting-edge science, and modern birding. We were particularly impressed to learn how scientists today can use older specimens to investigate questions not even thought of when the birds were collected decades ago. For example, the museum’s extensive series of Southwestern Willow Flycatcher nests and eggs, collected in the last decades of the nineteenth century, preserves priceless baseline information about that now-endangered subspecies’s historic populations, distribution, habitats, and habits—even down to the long-dead parasites still lurking in the the nests! Equally fascinating were some of the museum’s ‘teaching’ specimens. Many of these are from birds unaccompanied by even the most basic data, making them nearly worthless from a strictly scientific standpoint. But when such specimens are prepared to emphasize one or two salient features—the two-in-front, two-in-back toes of the Greater Roadrunner, or the precise underwing pattern of a juvenile Zone-tailed Hawk—these specimens can serve as excellent illustrations of basic principles important to the field birder as well. While the tour participants enjoyed a brief introduction to the University’s mammalogy and herpetology collections, Tucson Audubon Society leader Rick Wright assembled a number of seasonally appropriate bird skins for closer, hands-on examination. We had the opportunity to compare the size, tail shape, back pattern, and breast pattern of juvenile Cooper’s and Sharp-shinned Hawks, noting how the precise shape and pattern of individual feathers contribute to larger patterns visible in the field. We also discovered that American and Rufous-backed Robins, otherwise so deceptively similar when seen from beneath, can be reliably distinguished by the extent of streaking on the white throat. And a row of pipits served to remind us that we need to be on the lookout this time of year not only for Sprague’s Pipits, but for japonicus American Pipits and for Red-throated Pipits as well! We moved on, inevitably, to sparrows, one of the most challenging and exciting groups to spend the winter here in southeast Arizona. Two dingy skins turned out to belong to a Chestnut-collared and a McCown’s Longspur. In both, the distinctive tail patterns were invisible, but we found that we could identify them easily by the size of the bill: large and swollen in McCown’s, relatively slender and Spizella-like in Chestnut-collared. We then searched for other subtle marks that might be useful in good field conditions, and found that the spacing of the primary tips visible beyond the tertials on the folded wing differed consistently between the two species. Thank heaven for spotting scopes…. We also enjoyed a leisurely comparison of Baird’s Sparrow and Savannah Sparrow. While head pattern is a well-known and generally reliable field mark to distinguish the two, we were struck even more by the difference in back plumage, with Savannah quite plain and finely streaked, and Baird’s dramatically marked in black, chestnut, and gray. The bird lying between these two on the table, however, called us back to humility with the realization that not all birds can be identified even in the hand: with a rather Baird’s-like head pattern and a Savannah-like back, this skin had been identified on its tag as both a pale Savannah Sparrow and a hybrid between that species and Baird’s! Not all identification problems are at the level of species, of course. We compared one of our local fallax Song Sparrows with a strikingly darker and heavily marked individual from Pennsylvania, and had a rare opportunity to examine "Red" and "Slate-colored" Fox Sparrows side by side. We concluded our session with an ambitious challenge, namely, to work on the field separation of Grasshopper Sparrow subspecies this winter. As one participant remarked as we left, museum birding is a whole new way to look at birds. But it is a way guaranteed to make us all more careful and more knowledgeable observers in the field this winter, and all year ’round.
Rick Wright and Tucson Audubon Society offer sincerest thanks to Tom Huels for his kind invitation to visit the collections, and for an outstanding introduction to the importance of natural history collections in general.
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