Sunday, September 25, 2011

Where did all the birds go?

An unexpected by-product of Tropical Storm Irene is the disappearance of many songbirds from our corner of Vermont.

We were so distracted by the storm’s messy aftermath that it took a while to realize that things had gotten really quiet. I saw birds as soon as the storm was over—the usual blue jays, mourning doves, and chickadees, plus a flock of (presumably) migrating flickers, as well as the pileated woodpecker, who made his first appearance in years although we hear him often—but the sparrows and finches and thrushes went AWOL. My bird feeders stopped needing refills, and the mornings and evenings grew eerily quiet. What happened to the other birds?

Yes, it’s migration time, which normally changes the backyard equation. But the numbers are way down, too abruptly. I keep note all year, and any time my mom visits we do a formal checklist. So we know, from past years’ records, who should be in the neighborhood.

Our range for any year is 35-42 species at peak of spring/summer, down to 15-19 in depth of winter. In the transition times, we average mid-20s. Yet two weeks after the storm we counted a mere 16 species over 4 days of good weather, with the wildflowers, fruits, and foliage still in full bloom and insects aplenty.


It’s a well-known phenomenon that big storms displace birds, sometimes well outside their normal range. Birdwatchers take advantage of this to expand their life-lists. Indeed, an online search for information showed many reports of southern seabirds blown inland by Irene. There was no mention, however, of land birds blown out to sea.

Of course, only sailors and fishermen would notice, and they probably aren’t plugged into the bird-sighting network. So we will likely never know. It’s worrisome, though, because despite Irene’s catastrophic rains, the storm wasn’t particularly violent in these parts. The wind portion of the event was short and within the scope of ordinary weather. Habitat damage was localized; in our area, just spot road destruction and a few downed trees. There’s nothing to suggest that our birds lost food or shelter, or gained predators, or were simply blasted away.

So where did they go?

All I can think of is the storm mass was larger and more powerful than I understand, and sucked many migrants way off track, and they kept going from wherever they landed. Birds that I recognize as migrants, such as goldfinches, hummingbirds, and phoebes, have been popping up in onesies and twosies but just passing through. The other day we saw a kettle of hawks circling high, with a skein of geese even higher above them. But the normal routine of waterfowl gathering and honking has not occurred at all.

We haven’t seen one song sparrow, which is usually the first to arrive and last to leave and can be utterly relied upon for a daily appearance. The juncos, which started coming a month ago, disappeared again overnight. A house wren, one of which had been ubiquitous and constantly singing before the storm, showed up for one day a few weeks after. And the wood thrush and veery, who normally stay until a killing frost, are long gone. Even the robins are missing. Ordinarily, we see or hear several a day, but I’ve only noticed three in the weeks since the storm.

We’re down to resident winter birds already. Ravens and barred owls, who live here year round, tend to be noisy and visible after the migrants have shipped out. Yep, there they are, almost every day now. The woodpeckers, chickadees, and nuthatches never depart, and they too are increasing activity. Just this morning, though, I spotted two chipping sparrows in the garden after many days of conspicuous absence. They are probably migrating, like the hummingbirds glimpsed last week, so that’s I suspect that’s it for them.

It will be interesting to see who comes back in the spring. I hope there were no big population wipeouts, and all the birds currently absent are happily in transit somewhere else.

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