Sudden hammering made me jump. Above the forest darkness, a pileated woodpecker leaned out from a high larch snag, braced against the trunk by its specialized, stiff tail feathers. This was the first time I had seen this big white-and-black bird, the “cock-of-the-woods.” There was ample evidence of his work: the deep, oblong excavations in the trunk and the pile of large wood chips at its base, both characteristic of this species. Again he hammered, and I could see the chips falling. After a little edge-work around the hole, he extracted a grub and flew off, yammering against the advancing dark. Near a stream I stopped to sit down, to listen to the water and maybe catch sight of some small animal. Across the narrow defile, from a slope dense with young hemlock, came the buzzing note of a varied thrush. Several notes followed, all on a different pitch, all drawn out, level and clear; the quality was pure but songless, disjointed, deliberate, like someone testing the reed of a strange woodwind. There seemed no gladness in the heart of this thrush. The song was dark, haunting, lonely. On the trail ahead I could make out a bird hopping rapidly along. After passing the spot I could hear its song. There couldn’t be a hundred meters between us, yet it seemed to be coming from a great distance. I listened for as long as it would sing. I tried to hear it for what it was, a male Swainson’s thrush proclaiming its territory. But the ethereal, flute-like phrases seemed an evensong made not for man’s ears but only for the forest itself. I hurried on after the bird had ceased. It was getting dark beneath the trees, but I was beginning to be aware of creatures underfoot, the mad dartings of shrew and vole, more imagined than seen. When a deer mouse jumped away I got out my flashlight. Soon the beam caught a woodrat sitting atop a fallen log. The light didn’t bother him in the least; as I approached, he picked up his bushy tail in his forepaws. Whiskers twitching, he looked more caricature than real. Then he bounded off the log with graceful, arching hops, and disappeared into the night. Against a patch of sky that appeared in a clearing, I could make out bats, circling and dipping like swallows. Locating a hovering moth, I kept the light beam on it until it vanished into a furry streak of silence. It was time to head back. By now it had become utterly dark within the trees, a moonless, sightless, alien world, given over to the marble-black eyes of the small night mammals and the creatures that hunt them. I thought of the strange, unseen societies of the flying squirrels, the nocturnal counterparts of red squirrels; of the great-horned owls, inspecting the same ground the goshawks scanned during the day. Perhaps a foraging red fox moved through the darkness nearby, or a coyote on night patrol.