July 21, 2005

The Flycatcher's Paradox

M. and I came home from a trip in mid-June to find a Cordilleran flycatcher (formerly known as a Western flycatcher before the "splitters" got involved) building a nest under a rafter of our front porch roof, where a telephone junction box makes for a platform.

Back in the mid-1990s, another of the same species had built a nest in the same spot, but until this year, no flycatcher returned. It could not be the same female, surely, but we had to wonder if it was one of her descendants. Or maybe not.

She sat her eggs, even with big dogs barking on the porch, our comings and goings, hot days, thunderstorms, and all the rest. They hatched about a week ago, as the Mason Gulch Fire was coming under control. Two of the three chicks are barely visible in this photo, as sightless, gape-mouthed, little grey-feathered creatures.

When they hatched, the male showed up, and the adults both bring insects to the nest.

The flycatcher's paradox? When the female was sitting on the eggs, she would return to the nest from a hunting trip in stages. First she landed on the telephone wire that runs from the porch to a utility pole. Then she would hop about half the distance to her nest, watching for danger. Then she would hop half of the remaining distance. Her actions made me think of Zeno's Paradox--of Achilles chasing the tortoise. If the flycatcher hopped each time half of the distance to her nest, would she ever reach it?

No comments: