It's comical. It's absurd. It's a double-taker. I'm referring, of course, to the long-billed curlew's bill. How the process of evolution produced such a farcical-looking device on the front of this bird's head is a puzzler.
What's more of a mystery is that the male seems oblivious to the female's even longer bill than his because he's completely enamored with her.
The curlew's bill is six to eight inches long, very thin, and curves toward the ground. A tiny bulb at the tip helps the bird sense prey movement as it probes in sand or plucks items off the ground. The bill's length allows the species to reach the deepest prey available to shorebirds.
Long-billed curlews are North America's largest shorebird species, weighing over a pound and stretching nearly two feet from the tip of the beak to the tip of the tail. The female's bill is a third of that length and she outweighs her mate, too. Both birds are a warm golden-cinnamon color heavily notched with dark brown.
While they might be found along Great Salt Lake's shore, another reliable place to see them is in the sparse dry grasslands along the road to Bear River Migratory Bird Refuge, where males are busy using their three-foot wingspans to conduct courtship flights over their territories.
A male takes a few running steps and is aloft, exposing his cinnamon under wings and dark wrist patches on the topside. He aims high, at an angle greater than 45 degrees, and reaches an altitude of perhaps a dozen meters. At his high point, he sets his wings in a curve and glides steeply downward, only to repeat the flight again and again, scribing an invisible sawtooth path in the sky.
The purpose of his flight is both to impress a female watching from the ground and to deter rival males from competing for her or for his patch of earth. When he lands, he slows to a stop with a few running steps and prolongs his wing extension high over his back, folding them slowly as if to show off his cinnamon wingpits.
I watched a more intriguing courtship ritual between curlews on Antelope Island a few years ago. A liquid, clear, bubbling call came from the direction of two curlews, the male of the pair holding his cinnamon and black wings high. He lowered his wings and his sex was immediately apparent. He was a shrimp in comparison to the robust female who was easily 25 percent bigger. Her bill was much longer than his, too.
The female turned her back on her companion and began to walk across the low marsh grasses with a stately air. The smaller male didn't just follow -- he danced. He bounced up and down on those long legs as he quick-stepped around her. She continued her graceful stroll while trying to ignore him.
Most of the time the male danced from side-to-side a step behind the female, stretched his neck to her and ... ahem ... nibbled her tail feathers. His open beak snapped on one side of her tail and then the other, shaking his head all the while. While the scientific word for the display is shaking, I much prefer to call it nibbling.
Alas, the female was annoyed. Perhaps it was too early in the courtship season for her to be nibble-ready; had she been receptive to him, she might have settled into the grass and raised her tail, a signal for him to copulate with her.
Instead, periodically she'd whip around, run a step or two toward her eager suitor with her preposterously long beak open and snap at him while issuing that clear bubbling call.
A bird whisperer might interpret the call as "Back off, you little twit!"
The male knew exactly what her snapping meant. He retreated a few steps and raised his wings defensively each time his beloved whipped around. But when she resumed her stately walk, she exposed that beautiful nibble-magnet of a tail. The male fell in behind her and resumed his side-to-side dancing and nibbling.
She must have had enough. She launched into the air, flew a wide arc and gave a long series of clear bubbling notes, followed by a more familiar call for which the species is known: "Leeee! Curleeee! Curleeee!", perhaps leaving her despondent suitor to nibble another day.
Kristin Purdy can be reached at gobirding@comcast.net.
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