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Cross-country: The Discovery, and Probable Disappearance, of North America’s Newest Bird

Published as “The West’s newest bird species has a beak like a crowbar” in High Country News on July 12. 2017. 

At 6:30 one morning in early July, Craig Benkman, a University of Wyoming ecologist, began to stalk red crossbills in the South Hills of Idaho. We were between Twin Falls and the Nevada border, outside a cabin tucked into a forest near a minor ski hill, Magic Mountain. He and several of his graduate students had quietly strung ornithology’s signature ploy, a diaphanous mist-net, between two metal poles. It hung nearly invisible, low to the ground, below two lodgepole pines. Several of these sanguine birds — a large finch with a beak that looks curiously off-kilter, one mandible overlapping the other — were resting in the grass by a salt lick. Crossbills feed exclusively on the seeds of conifer cones, and must supplement their diet with sodium. “It’s like how, in the Sierra, marmots chew on your sweaty boots,” Benkman explained. Typically the birds might swallow a little clay from the roots of a fallen tree for salt, but here cabin owners had arranged mineral blocks in the grass to lure moose and deer nearer to their windows. Benkman peered through his binoculars at a male sitting with several others beside the net, all of them looking up warily with glossy black eyes. The male’s domed head, breast and rump were the crimson of an heirloom tomato, flecked with orange, with yellow ochre. “Oh,” Benkman said, in a rising whisper. “An unbanded one.”

Six feet four, thin and bespectacled, Benkman has a hushed voice and a sense of humor as dry and pleasant as the sagebrush- and wildflower-spotted South Hills. He is an old-school naturalist and an intuitive, holistic thinker, something increasingly rare in this era of computational biology and specialization. Walking the South Hills, he refers to minute flowers by their Linnaean names and muses about the West’s big ecological picture as his jeans swish through the fragrant scrub. For more than 30 years, he has studied crossbills across North America, as well as in aviaries, and for the past 20 summers, he has visited this remote mountain range on the edge of the Great Basin, where he and his students aim to capture as many crossbills as possible and mark them with colored leg bands. When he received the prestigious E.O. Wilson Award from the American Society of Naturalists in 2014, the judges remarked that his crossbill work “rivals long-term field studies of the Galapagos finches.”

The mist-net swayed, reminding the nervous birds in the grass of its shadowy presence. “I wish the wind would just stop,” Benkman said, as if to the wind itself. “This is where I think you need to be aggressive and try to spook them. You take off your shirt and throw it — make it look like a goshawk.” He started to peel the plaid shirt from his long pale torso, but I offered up the green fleece I’d shed already. Benkman tied it into an aerodynamic knot, a mock raptor. “For an unbanded bird?” he said. “You can’t just stand idly.” He began to slink circuitously toward the salt lick.

Read the rest at High Country News.

Check out Craig Benkman’s lab page.

Listen to a six-minute podcast based on this story by Laura Erickson of the Cornell Lab of Ornithology.