Barbara Bilsborough firmly held a small red cardinal that she plucked moments earlier from a net strung across a small clearing in the woods encircling Harford Glen Park.
"This is this year's bird. It was hatched maybe a few weeks ago," she said over its squawking protests.
A dozen children looked on as Bilsborough clamped a silver band around the young male's leg and explained that tagging birds will helpstate and federal ornithologists track the birds' migratory behavior.
If the cardinal is sighted next year, Bilsborough said, she or another volunteer licensed by the U.S. Fish and Wildlife Service will again record its weight and wing span and examine it for clues to thehealth of the county's environment.
Giving students an appreciation for the county's environment is among the points of a summer camp launched this year by the Harford Glen Foundation and the county's Emmorton Recreation Council. Sponsors hope the 60 children who attendedtwo separate week-long sessions leave as hatchlings with an environmental consciousness.
Bilsborough's demonstration was part of a bird safari that 30 children ages 6 to 11 joined Wednesday and Thursday.
They also learned to make bird feeders from juice cartons and identify different species that rely on wetlands like Harford Glen's 75-acre swamp for their survival.
"This year, our spring migration was terrible," Bilsborough said. "Some days, we couldn't find any birdsat all."
She speculated that torrential rains around the Gulf of Mexico earlier this year might have disrupted the migration of some birds that usually make Harford Glen's 300 acres their summer home.
But instructors wanted the campers to know that the park that stretches along Route 24 north of I-95 is not just for the birds.
"What we try to teach them is that anything you put on the land eventually makes its way into the streams and rivers and eventually the Chesapeake Bay," said Helen Richick, a Harford Glen boardmember who developedthe camp program.
The Harford Glen wetland gives campers a perfect example of what goes wrong when people don't pay enough attention to what they put on the land.
Formerly a lake navigable by small boats, the wetland has filled with much sediment over the past two decades. In many places, bass have barely a foot of water to negotiate between the murky bottom and the algae, where they chase rude-sounding bull frogs and other prey.
Campers learned that forests and wetlands stop rain runoff from washing nitrogen and other nutrients into the waters. Nitrogen feeds algae that can choke out sunlight and the oxygen that aquatic life depends on.
The campers built their own miniature wetlands, using aluminum oven basting trays to create individual ecosystems.
A cup of water and a bag of dirt duplicated the problems of erosion and storm water runoff.
Campers created little swamps with brown-stained cotton swabs for cattails and a piece of green sponge-like florist foam to filter out sediment and impurities fromthe "rain." The hands-on instruction won a strong endorsement from 11-year-old Sarah Holdredge, who will attend sixth grade next year at BelAir Middle School.
"We learned a lot about the animals and the plants and wetlands and how they filter the water," she said. "It's better than just making arts and crafts because we go out in nature and understand it better."
Nature's no stranger to Sarah, an avid bird watcher who boasts recording 50 species in her journal during frequent visits to Harford Glen.
"I also saw a bald eagle this spring," she said, proudly swinging her shoulders back and forth to every word.
"It was sitting on a branch in a tree," Sarah said. "We thought it was a vulture at first but then we saw through the binoculars --it was an eagle. It was really neat. It was the rarest bird I ever saw."
Had she not attended camp last week, Sarah said she probably would have spent the time swimming in her back yard.
But she also said she will keep exploring the woods around her home with her little sister.
In that respect, Sarah's instincts are much like the cardinal she watched being tagged.
"They fly tremendous distances," Bilsborough said, holding the bird aloft to set if free. It immediately darted into a patch of wild rose bushes six feet away.
"But theyalso are very loyal to their nesting area."