Rusty blackbirds on rise
Unity College bird count shows migration change 

01/22/2008

UNITY -- Reports of the rusty blackbird's demise may have been overestimated.
Bird enthusiasts who took part in the annual Christmas bird count in the Unity area last month once again came across the rare songbirds.

That was surprising for a species that is believed to have dwindled in number by 90 percent during the past 20 years and historically travels no closer to Maine than New Jersey in the winter, said Unity College professor David Potter, who has headed the Unity bird count for 11 years.
 
"This is the third year we've seen (rusty blackbirds) at Unity College," Potter said. "Some of the experts are surprised they're wintering in Unity, Maine."

According to the National Audubon society, rusty blackbirds migrate north in the spring, settle into nests near still water, then migrate to southeastern states in the late fall.

Until recently, rusty blackbirds had never been spotted in Maine during the December count, Potter said.

But in addition to the four spotted in the Unity count last month, rusty blackbirds were found this year in Blue Hill and Portland. Scientists are unsure why the birds' migration habits have changed.

"Maybe they're moving northward," Potter said. "Maybe it's an indication of habitat change or climate change."

The shifting patterns could mean that the birds are not decreasing in numbers as once believed, Potter said.

"It's not necessarily that the rusty blackbirds are decreasing at these rates," he said.

"But they're not being reported in their usual breeding grounds."

The National Audubon Society organized the bird counts between Dec. 14, 2007, and Jan. 5 throughout the country.

The Unity bird count, which is centered near the U.S. Route 202 bridge over Sandy Stream, took place Dec. 14.

Thirty-eight counters fanned out over a 15-mile circle for 10 hours, cataloguing every bird that crossed their paths.

The count included a total of nearly 180 driving miles and 16 miles walking.

Counters found 2,631 birds, 44 different species, led by a total of 440 black-capped chickadees.

The statistics are collected from the around the country and posted at the National Audubon Society's Web site (audubon.org) where everyone from casual observers to influential ornithologists look for trends.

Unity observers were surprised by the number of empty or missing bird feeders, Potter said. Surveyors use a variety of methods to locate birds, from walking through the woods to driving down back roads.

Private bird feeders also are a valuable tool for counters, Potter said, but this year more bird feeders than ever were found empty.

"Some of the spots had feeders still hanging there, but there was no feed in them," Potter said.

He speculated poor economics, a deep snowpack and an aging population of bird-feeder keepers may be responsible for the decline.

Regardless, it is unlikely birds have been affected by the dearth of readily available food.

"They'll use what's available but if you stop feeding them, they'll go somewhere else," Potter said.

Craig Crosby