Migrating birds look like cloud cover on weather service radar

This week I’d like to share some awe-inspiring information and compelling sights I’ve had the privilege to view over the last several days.

The first is an e-mail on the Maine Birding list-serve sent from Bill Sheehan, in Aroostook County. Bill is a keen observer of birds, climate, and environmental conditions, eloquently describing his observations and sharing them with fellow birders. The subject heading of the e-mail read: “Another great migration night tonight.”

In the body of the e-mail, Sheehan wrote, “It’s absolutely clear in northern Maine but the birds on the radar make it look overcast! I’ve heard a dozen birds in just a few minutes.”

He then included a link to Caribou’s National Weather Service radar images. A huge, dense, spreading cloud appeared over a satellite image of the state.

No, it wasn’t actual cloud cover. It was hundreds, perhaps thousands, of migrating songbirds, which take advantage of the cooler, calmer night air in which to fly their marathons. If you happen to be in their flight path and you live in a quiet area, you can hear them passing overhead; they emit brief flight calls as they travel. Very experienced birders can identify which birds are passing overhead in the dark, each by the type of call note it has.

I got goosebumps imagining millions of birds all over North America leaping into the air at once to begin their awesome journeys south.

The National Weather Service radar images are available at its Web site: www.weather.gov. Once on the site, go to the menu on the left and click into “radar,” which is listed under “observations.”

A magical night

One evening last week I decided to go for a walk around the UMaine cornfields off Route 2. It turned out to be one of the most beautiful evenings I’d ever seen.

After completing the loop around the field, I returned to the small wetland that bisected it. A harsh, scolding “tchat” note called my attention to the presence of a male common yellowthroat warbler half-hidden in the marshy vegetation. Its bright yellow head and chest and black mask made it easy to identify, as did its vocalization; this type of call note is often given whenever the bird detects something out of the ordinary in its vicinity.

Fall songbird migration was settling into full swing, and I wondered if the bird was a resident that hadn’t left yet or a traveler from farther north that had stopped to rest and refuel. After the breeding period between May and July, common yellowthroats go through a complete molt around August. They then head south during the months of September and October.

As I headed down the narrow, grassy path through the middle of the wetland, I heard faint, whispered snatches of the yellowthroat’s song; a reminder, and promise, of another spring season to come. The sun had set; a blanket of mist hung over the wetland. I happened to look over my shoulder and beheld the full moon just cresting the horizon.

Because it was so low in the sky, the moon appeared twice as big, glowing a brilliant orange-yellow. Shining through a halo of mist also turned golden, it appeared as if it were emitting the light of the sun, instead of just reflecting it. It was as if the sun had suddenly, incongruently, reappeared in that darkened eastern corner of the sky. The effect was extraordinary.

Crickets chirped around me, while mallard ducks came gliding in to spend the night in the wetland. The warblers had fallen silent. The ghostly forms of whitetail deer bucks slid through the mist.

It was a magical night as the earth allowed me a peak at her secrets.

BDN bird columnist Chris Corio can be reached at bdnsports@bangordailynews.net