GETTING YOUR ATTENTION

Wednesday, July 16, 2008

The ruffed grouse exploded in every direction from directly in front of me, their wings whirring in a noise that seemed to echo through the deciduous woods. There must have been at least nine or 10 of them. My heart just can’t stand surprises like that anymore.

Off to the left came a sound not unlike a small mammal in distress. I peered into the dense undergrowth and saw nothing, but heard a rustling and beating of leaves as though something was thrashing around. The noises sounded like a baby crying. I followed the noise, guessing by now it was the female attempting to lead me away from her young. I followed her cue, as she continued to whimper and move through the shrubbery. The moment I would turn and start off in a different direction, her cries would intensify, then subside as I continued to play along.

Perhaps the first species to come to mind when we speak of distraction displays is the killdeer, with its famous broken wing act. The killdeer feigns a broken wing in hopes of luring a predator away from its nest or young. The parent killdeer is experienced and knows just how far it can take this act before it, too, must flee, or be caught. But the killdeer has to make a judgement call, whether to lead the perceived danger away, or simply stay put on the nest and hope she will blend in enough with the habitat to go unnoticed.

This "freezing" tactic may work for other birds too. A mallard’s nest near the lighthouse on Main Duck Island off the coast of Prince Edward County some years ago, appeared to have been deserted. The nest had been exposed by vegetation clearing efforts near the lighthouse as a helicopter full of maintenance workers was to arrive that day to service the solar system. As the helicopter landed the wind from the rotating blades sent up a flurry of empty zebra mussel shells, grass and twigs, sandblasting and damaging the nest even further. There was even one broken egg. Two weeks ago, the female mallard was perched on her damaged nest, incubating what was left of her clutch of eggs, completely exposed, but she never moved as we walked beside her nest. Few of us even saw her, until I mentioned it.

Mostly, birds prefer to lead predators away, and they do it in a variety of ways. The killdeer we are familiar with, and the ruffed grouse I saw tried it with very painful and mournful sounds. Vesper sparrows nesting in hay fields on our farm many years ago would flush from the nest and seemingly tumble head over heels as they flew clumsily at low altitude over the alfalfa, disappearing into the foliage some distance away. One couldn’t help but divert their attention to these weird antics.

Displays of other birds give the impression of a tiny mammal running through the grasses. Purple sandpipers that nest on the ground in the Arctic, perform a "rodent-run" display. The bird drags its wings, creating the illusion of a second pair of legs, erecting its feathers providing some semblance of fur, and squealing while it dodges between imaginary barriers.

One that does not resort to distraction displays is the American coot. It prefers to face its danger, whether imagined or otherwise, be it a passing mammal or a passing airplane. It does so by erecting its feathers, effectively doubling the size of the bird. Likely, we have all seen loons and swans chauffeuring their young upon their backs. Although initiated by the young by simply clambering aboard and hanging on for dear life, some adult birds feign carrying their young, leading away predators in that manner, while the actual young are safe somewhere else in an undisclosed location. How they actually do this is uncertain; we are still learning.

But are these tactics that have evolved over thousands of years enough in a world of shrinking habitat, feral cats, and other dangers that lurk out there? Some ground nesters continue to decline, despite these clever distraction displays.