Tuesday, June 26, 2007

A bird’s blessing

The American Goldfinch is a patient bird, at least when it comes to building a home and raising a family.

Each season, goldfinches are among the last of our birds to establish nests. Most others already have fledglings – you can hear them now, squeaking and whining at their parents to feed them. But goldfinches are just getting their nest work underway.

Why? The goldfinch seems to time its domestic duties to the season of the thistles, those prickly wildflowers most people hate. Early thistles are just now going to seed, producing the super-soft down that is so opposite the thorns that bedeck the plants. Goldfinches love thistle down as a material for lining their nests.

After the eggs have hatched, thistles provide their second benefit: Food. Goldfinches are mostly seed-eaters and they delay raising a family with a bunch of hungry mouths to feed – until mid-summer when the season of seeds is well underway. Probably their favorite seed is the thistle.

“Cursed is the ground because of you,” God told Adam in the Garden of Eden. “Thorns and thistles it shall bring forth for you.” Clearly, a man’s curse can be a bird’s blessing.

Monday, June 25, 2007

Sound of the Veery

I heard a Veery on Sunday. That may not sound like a big deal, but it’s the first one I’ve heard locally in more than five years.

And hearing them is often all you do, for these brown thrushes are somewhat secretive and stick to woodlands where they can be hard to spot.

However, their song is one of the most distinctive and easy to recognize of any of our migrants. It’s a flutelike cascade of notes, seeming to echo as if they were sung through a long open pipe. Once you’ve heard the song, you never forget it.

Time was when the song of the Veery was a sure sign that spring had settled in. It was something to listen for. But Veeries are in what the Cornell Lab of Ornithology calls a “slow decline” throughout their range.

In winter, that range includes a large area of central and northern South America, much of it rain forest, which, as we all know by now, is being cut down. Ornithologists suspect that this “rapid habitat conversion” is reducing the Veery population.

Up north, these birds may also be suffering from the deer overpopulation. Veeries nest on or near the ground and thus prefer woods with dense understory that provides a degree of camouflage and protection. Overpopulating deer have stripped so much of the understory of our woods that Veeries may be having difficulty finding suitable nesting sites. (However, the latest statistics from the state of Connecticut indicate the state’s deer population may be in decline from a peak of 75,000 a few years ago to a current estimate of 62,000.)

Veeries have also suffered from nest parasitism by Brown-headed Cowbirds, but the latest studies on cowbirds are finding that these birds may also in decline. So it’s likely that the habitat destruction, in both winter and summer ranges, have been affecting the Veery numbers in our neighborhood.

Wednesday, June 20, 2007

Are deer down?

Connecticut’ deer population has been stabilizing, maybe even declining. So says the Wildlife Division of the Connecticut Department of Environmental, which in February completed its latest aerial population survey.

Officials put many qualifiers on their numbers, including the fact that the aerial survey looks at only one percent of the state’s total deer habitat. Nonetheless, from 1993 to 2003, the estimated winter deer population rose from 49,472 to 75,771. Last winter, the estimate was 62,163. If the state’s system of surveying is reasonably accurate, that would be a noteworthy decline.

We are still in the most deer dense part of the state. Fairfield County has an estimated 29.4 deer per square mile, the highest density of any of the 12 state zones. The statewide average is 17.

Wildlife officials also watch data on hunter kills, deer-vehicle collisions, and even “homeowner concerns,” and all also seem to indicate the population is at least stabilizing.

Why? The state has “adjusted deer seasons, modified bag limits, and encouraged the harvest of antlerless deer in high deer density areas,” DEP said. “Wise deer management results in healthy deer populations and productive wildlife habitat.”

In a word, the state seems to be saying, hunting.

Wednesday, June 06, 2007

The Big Stink

There’s been a big stink at the University of Connecticut lately. No, it’s not some scandal or controversy, but the blooming of a Titan Arum – two, in fact – at a university greenhouse. Only twice since the 1930s has this species flowered in the Northeast, and UConn has two in one season.

Natives of Sumatra, Titan Arums bear huge blooms that literally reek. Both in their foul odor and reddish color, the flowers mimic carrion, all in an effort to draw flesh-eating flies to pollinate them.

However, you don’t have to go to UConn or Sumatra to see the same technique in action in our own woods. Early each spring, our wetlands are bursting with Skunk Cabbage flowers, another Arum that uses exactly the same technique – carrion color and scent – to attract flies.

Still another spring stinker is Purple Trillium, a fly-baiter that may qualify as the worst-smelling wildflower in North America. But its odor is not a defense and unlike an Arum, the trillium is not bitter-tasting. Unfortunately, hungry deer won’t turn their noses up at a bad smell, and have been eating our trilliums into oblivion.