Adapted from Jim Conrad's Naturalist Newsletter of October 8, 2007, with notes made during a visit to Nevado de Toluca Volcano, México State, MÉXICO

The tent makes a great wildlife blind. At dawn last Wednesday just as sunlight began flooding the top halves of surrounding pines, three or four Western Bluebirds -- permanent residents here -- arrived at an open, flat clearing near my tent. They perched on low limbs and atop tall weeds, swooping onto the ground when something worth eating was spotted.

When sunlight flooded the whole area, five to seven Yellow-eyed Juncos joined the bluebirds, mostly foraging for weed seeds on or near the ground. The whole mixed flock was a diffuse, informal affair seldom with more than three or four birds visible at one time, each bird giving its neighbors plenty of space.

When the air warmed a bit two Townsend's Warblers streaked into a chest-high pine right beside my tent, one chasing the other as if it were Spring courtship time, not the beginning of their overwintering period after spending summer somewhere between southeastern Alaska and the US Pacific Northwest.

About the same time two Hairy Woodpeckers peek-called, briefly one chased the other around a pine trunk, one flew off but the other remained to forage among the orange "misteletoes" heavily infesting all the slope's pines. Then a tiny Mexican Chickadee silently and furtively slinked through a little pine near my tent. Throughout all the above activity American Robins nasally clucked in treetops all around, though I never saw one.

For about an hour the mixed flock put on a circus in and around the sunlight-flooded clearing. But then suddenly the sound of a logging truck intruded. Every bird changed what he was doing and most flew to perches to see better, cocking their heads this way and that. The truck came no closer than a hundred yards but it was close enough to cause the flock to dissolve before I realized what had happened. Into the icy, pine- scented air drifted the odor of hot motor oil.

And then there was silence, except for the wind.