HOLDEN, Maine- — Saturday was hot and breezy, a perfect day for counting butterflies.
Shortly after noon, a small troupe of enthusiasts could be seen wandering haltingly along the garden paths surrounding the Fields Pond Audubon Center. They carried cameras, binoculars, field guides and notepads. Among the brilliant bee balm, the fading lupines and the drooping milkweed, they searched for the fleeting flutter of colorful wings.
“Oh, look, there — one landed,” exclaimed nature center visitor Jake Ward of Carmel, pointing into the tangle of flowers and grasses. “Oops, wait, he took off.”
The occasion marked the day of the 2010 North American Butterfly Count. The nature center at Fields Pond lay at the center of a 7.5-mile radius circle that was being surveyed by Fields Pond staff and volunteers. Among the butterflies most likely to be spotted were white admirals, red admirals, viceroys, American coppers and several species of fritillaries.
“There are three big fritillaries in Maine,” said Pat Snyder of Stockton Springs, a Fields Pond volunteer who headed up the procession and is in charge of the local count. All fritillaries, large and small, are a deep rusty orange with a checkerboard spray of black spots across their wings. But the Aphrodite fritillary, Speyeria aphrodite, has a lacier look with fewer black spots. The wings of the Atlantis fritillary, S. atlantis, sport a formal black edging, and the underwing of the great spangled fritillary, S. cybele, has a pale diagonal streak.
Later, wading through the knee-deep fields of vetch and dogbane, the group identified several species, including a common sulfur, a northern pearl crescent, some cabbage whites, and several types of skippers, whose wings rarely lie flat at rest but instead close upright above their torso, the thorax.
Sulfurs are particularly attracted to the nectar of leguminous purple vetch, Snyder said.
Goldenrod, asters, oxeyes, fleabane — “these are all plants people might think of as weeds and pull up,” she said. “But they bear flowers into the fall, and the butterflies need those fall flowers, too.”
Among the counters was former Fields Pond manager Judy Markowsky, a familiar fixture in local environmental circles. Markowsky said many people assume all large, orange-colored butterflies are monarchs, but the species is actually not common in Maine.
“One summer, I saw quite a few here,” she recalled, “but not since.”
Snyder said climate change, human development and the related loss of wetlands may undermine butterfly populations. Humble woody plants such as willows are an important food source, she noted.
“At the nursery, they won’t sell you a native willow, but they’ll sell you one from China,” she said. “The butterflies know the difference.”
Results of the 2010 North American Butterfly Count will be available later this year.