Deep in the woods Wednesday afternoon, Jean Fry exhaled air through clenched teeth and warbled, "Pish . . . , pish . . . !" Almost immediately, her call was answered by chirps from about 80 feet above.
"Chickadees, three or four of them perched way up in the tree," Mrs. Fry said, as she peered through her binoculars and quickly recorded her sightings on a tally sheet.
Since dawn, Mrs. Fry and her husband, Larry, had been leading a small group of bird watchers through the Glen Cove area near Conowingo Dam for the 23rd annual Rock Run Christmas Count. Most of the participants were members of the Harford Chapter of the Maryland Ornithological Society.
The local census was part of a count that began Christmas Day in 1900 when ornithologist Frank Chapman and 26 other people counted every live bird they could find to protest the traditional and competitive holiday slaughter of birds, Mr. Fry said.
Each year since, the National Audubon Society has sponsored the Christmas Bird Count. The results of the collected data appear in the society's American Bird magazine.
"That database provides scientists and researchers with important information on changes in the bird population and changes in the environment," Mr. Fry said.
'Barometer of environment'
"Birds are the barometer of our environment. They reflect what's happening around us," Mrs. Fry said.
In his 20 years of bird-watching, Mr. Fry said he has noticed a population explosion of mockingbirds in this area.
"Mockingbirds get along with people, and their habitat isn't distracted by subdivisions," he said.
On the other hand, John Wortman, a veteran bird-watcher and member of the local bird club for more than 30 years, said he has noticed a steady decline of field birds -- "definitely a sign of increased development and new farming techniques."
"Larks have declined, and robins," Mr. Wortman said. "They like open areas."
A total of 51 area bird-watchers, ranging from teen-agers to senior citizens, made up the 15 groups conducting last week's count, said Dave Ziolkowski, who at age 20 is the youngest member of the club to organize the event.
Statewide, 22 counts are being conducted throughout the holiday season. Nationally, birds will be identified by about 50,000 volunteers at 1,600 locations, said Mrs. Fry, who is president of the Harford bird club.
'Brand new species'
Locally, the birders counted from dawn to dusk Wednesday, first prowling the woods for owls and then trying to identify as many species as possible. They hoped to beat the record of 96 species set in 1992.
"It could happen this year," said Mr. Ziolkowski. "Right now the record is tied, but we're still waiting for the results of one group."
Records might not have been broken, but two sightings of species not observed by the group before were part of the club's Christmas count history.
Dennis Kirkwood and his group of five bird watchers set out by boat at 7 a.m. to identify waterfowl on the Susquehanna River. But the first bird they saw was a peregrine falcon, on the Amtrak bridge.
"That's a brand new species for our history of counting," Mr. Kirkwood said. "The falcon has been seen for the past month or so, but had never been positively identified."
Two Thayer's gulls also were sighted for the first time at Conowingo Dam.
Bird counting is completed in the same area each year -- in a 7.5-mile radius of Rock Run in the Susquehanna State Park.
"For the data to be valid, it's important that the counting is done in the same area each year," Mrs. Fry said.
The Frys have been participating in the Christmas Bird Count for eight years and have led groups through the same area each year.
This year, their team sighted more than 400 birds and 40 species, from a yellow-bellied sapsucker and a hairy woodpecker to mockingbirds and white-throated sparrows.
Total count falls
While the number of species identified was about average, the total bird count for the group was down this year, Mrs. Fry said.
"For example, in our group last year we counted 880 Canada geese and this year only 27; blue jays numbered 23 last year and seven this year; and we sighted only three Carolina wrens this year, compared to 17 last year," Mrs. Fry said.
She attributes this year's decline in sightings to factors such as luck and weather.
"The weather has really been warm this year. Colder weather makes the birds more active," she said.
Although the group's tally was down, there were some pleasant surprises.
For the first time in their eight years of Christmas counting, the Frys sighted a hermit thrush, a small robin-sized bird with a speckled breast and rusty tail.
"We've seen one before, but never in the eight years we've been doing the Christmas count," Mrs. Fry said. "It's the highlight of our day."
For Sharon Golumbeck, who participated in the Christmas count for the first time, sighting a hermit thrush wasn't a big deal.