Every bird counts

From common urban pigeons to two majestic bald eagles perched in a tree at Hoopes Reservoir, every bird mattered Saturday when a team of volunteers went out to assess winter bird populations in a habitat-rich area of northwest Wilmington.

Since Dec. 14, other teams have canvased 15-mile-wide diameter circles throughout Delaware as part of the Audubon Christmas Bird Count. The idea: to get a snapshot of wintering bird populations.

Last year, the volunteers-- both in Delaware and other East Coast and Great Lake states -- captured the snowy owl irruption. Snowy owls normally spend the winter well north of Delaware. This year, two have been spotted in the state. Last year, there was at least one and possibly more, in each county. National Audubon scientists say that irruption was the biggest influx of snowy owls documented during the century and it lasted throughout the winter.

This year the National Audubon Society is asking volunteers to pay close attention to another species: Loggerhead shrikes with leg bands. The data collected in this part of the count will be shared with Wildlife Preservation CANADA for an on-going research project.

The volunteer survey which runs from Dec. 14 through Jan. 5 will include some 70,000 volunteer bird watchers who will count the types and numbers of birds they see in more than 2,400 locations.

In this rolling and wooded terrain in North Wilmington, team leader Bill Stewart, said there are 50 species they expect to see on a typical winter day.

"We definitely have the expected species, the target species" that we look for, he said.

But Saturday some of those were challenging to find: birds like the purple house finch and the red-breasted nuthatch. These are birds that people often see on their backyard feeders this time of year.

There were hundreds of Canada geese, two mature and one immature bald eagles and several red tailed hawks spotted and counted, European starlings, cardinals, blue jays, robins and kingfishers. They heard two species of owls in the hour before dawn and saw signs that others had been hunting from evergreen trees in a grove at Winterthur Museum, Gardens and Library grounds.

They searched near brush and yard waste piles for sparrows and other tiny birds. They walked along a wetland at a private estate, followed the banks of the Brandywine Creek and walked amid cut-over corn and soybean stubble. Few birds came easy, despite an unseasonably warm, clear and sunny day.

But even though the work was challenging, it is part of 115 years of data collection done by volunteers.

Audubon officials say it provides "the most comprehensive data set depicting the fluctuation, range and movement of bird populations across the continent." Scientists use the date to understand how bird populations are growing, declining and shifting range.

"The Audubon Christmas Bird Count harnesses volunteer power to gather knowledge that shapes conservation policy at enormous scales in this country. I couldn't be prouder of the volunteers who contribute each year," said Audubon President and Chief Executive Officer David Yarnold. "Christmas Bird Count data is becoming increasingly important not only in documenting current climate change but in predicting the future effects of climate change on North American bird populations. If we know what to expect, we can start taking action now to do something about it."

The national organization recently released a new report that predicts how climate change might impact the range of bird species. The report was compiled using 30 years of North American climate data and thousands of Christmas Bird Count observations along with the U.S. Geological Survey's North American Breeding Bird Survey.

Over the years, researchers have also used the data to track and identify birds that were in decline or recovering. The Christmas count helped researcher track the recovery of bald eagles, peregrine falcons and shifts in ranges and population size of several waterfowl species.

Last year, 71,659 observers counted over 66 million birds. Those birds included 2,403 species. Counts were done in all 50 states, throughout Canada and parts of Latin America, the Caribbean and the Pacific Islands.

The Christmas Bird Count was started in 1900 by ornithologist Frank Chapman. He came up with the idea as an alternative to the holiday "side hunt." The practice of the day was for teams to go out and see which could shoot the most birds. Chapman gathered together friends and suggested they count birds instead. The tradition started with 27 birders. Twenty-five counts were held that first day and the teams tallied a total of 90 species.

Stewart and his team -- Anthony Gonzon, of Middletown, Callum MacLellan, of Abington, Md., his aunt, Sarah MacLellan, of New London Twp, Pa, Mike Hudson, of Baltimore and Kim Steininger, of Chadds Ford, Pa. -- started the morning before dawn in search of owls.

They moved on to Hoopes Reservoir. There, they found a flicker, a gadwall, a pied-billed grebe and dozens of Canada geese, among the species.

"I've been birding this place for 40 years and it's just spectacular," Stewart said.

Then, he announced the first challenge of the morning: "Who's going to find the first bald eagle?"

"I've got a cackling goose," Hudson said.

And then out of the morning mist, there was a squeaking sound so Stewart and Steininger started to scan the horizon and the trees.

They were rewarded with two mature bald eagles roosting in a tree.

"There's a pileated flying in," Steininger announced in the next breath, referring to a pileated woodpecker.

"There's an immature bald eagle in the cove," Stewart said.

And so it went as the birders spotted species, after species.

"I gets me out going to places I would never go," said Sarah MacLellan.

And while the easy species were hard to come by, the team found some gems along the way. Most Delawareans can identify the chickadee. The species that they typically see is the Carolina chickadee -- the more southern of the two birds.

But by a brush pile at Winterthur, Gonzon heard the lower call of the more northern black-capped chickadee.

And while snow geese are common along the grain fields and marshes of Kent and Sussex Counties, they are more difficult to find in the rolling habitat of northwest Wilmington.

Gonzon picked out a flock in the distance near Brandywine Creek.

"Every year we get some unexpected species," Stewart said. "What just flew up?"

"Downy" woodpecker, Hudson replied.

Reach Molly Murray at 463-3334 or mmurray@delawareonline.com. Follow her on Twitter @MollyMurraytnj.