June 23, 2004|By Larry Carson | Larry Carson,SUN STAFF
Siberian tigers they're not, though the orange, white, red and black colors of the delicate, declining Baltimore checkerspot butterflies that just moved into a tent at the Baltimore Zoo are similar, and no less spectacular.
But butterfly advocates hope that the new winged residents, unlike the recently deceased tigers, will breed in their controlled environment. If they do, it could spark a comeback for Maryland's official insect, which has suffered years of damage from deer, who eat their host plant, and development, which also destroys habitat and separates butterfly colonies.
Two squads totaling 25 volunteers are trained and ready, said Steven J. Sarro, curator of birds at the zoo, who is excited about a new venture to help creatures that are drawing increasing public interest.
"It could be huge," Sarro said about the breeding experiment that officially began Saturday, when several caterpillars and adult butterflies caught in Garrett, Carroll and Frederick counties were moved to their new quarters - a beige, mesh-sided tent in a fenced-off corner of the alpaca pasture, between the pink flamingos and the ducks and swans.
Fourteen of the checkerspots' main host plant, the turtlehead, are growing in plastic pots. Three of the spear-leafed green plants are covered with white mesh "socks" to hold the butterflies and caterpillars where they can eat and lay eggs.
Before dying, the adult females lay their eggs on the underside of the turtlehead leaves. The eggs hatch during the summer and the young caterpillars eat the leaves where they emerge, molting periodically as they grow. Eventually, they crawl down the plant and burrow into the ground for winter. In spring they re-emerge, climb back up the plant and begin eating until they take flight. Only about 1 percent of eggs mature into adult butterflies.
"This is a specialized propagation area," Sarro said. If the experiment works and the eggs produce young caterpillars, they'll be moved to the zoo's turtle bog for the winter.
"Right now, we're just getting our feet wet. We're caterpillars now," he said of the breeding project. It is being undertaken with members of several advocacy groups, including the Washington Area Butterfly Club, the American Zoo and Aquarium Association, the National Fish and Wildlife Foundation, Environmental Defense and the Maryland Entomological Society.
The zoo is also a member of the Butterfly Conservation Initiative, a national effort to help the fragile creatures.
Pat Durkin, co-founder of the Washington club and coordinator of the Baltimore Checkerspot Butterfly Restoration Project of Maryland, said she collected nine more butterflies this week to add to the initial half-dozen, which were at the end of their typical 10-day life span.
"Our long-term goal is to get a wild colony going on the zoo grounds. If we get enough, we'll start returning butterflies where colonies have diminished," she said. In time, new colonies can be started.
With 500,000 visitors a year, the zoo is also well positioned to tell people about the checkerspot's plight and "raise awareness that the state insect is not in great shape," Sarro said. A sign featuring a picture of adult checkerspots informs visitors passing the tent that "With luck and care, these winged jewels will soon be fluttering around our zoo."
Yesterday, passing children pointed excitedly and exclaimed to their parents, "Baby butterflies!" - although none was visible.
The Maryland General Assembly declared the checkerspot the official state insect in 1973, because its hues are similar to the family colors of Maryland's founder, Cecilius Calvert, the second Lord Baltimore.
The butterfly is not on an endangered species list, but it is in serious decline. Last year's cold, damp spring didn't help, said Richard H. Smith, a society member engaged in a three-year survey of butterfly populations.
"We're finding that compared to 25 years ago, many species vulnerable at the time have declined even more," he said. "There are very small numbers compared to what I remember."
Previous attempts to breed the insects in Howard County failed, though Sue Muller, the county recreation official who has organized the attempts, is cultivating turtlehead plants in enclosures protected from hungry deer, waiting for new breeding stock.
Muller will help with the zoo project one day a week, she said. And if the breeding works, "maybe in three years" there will enough butterflies to transplant to the habitat she is nurturing.
By the end of July, "once the temperatures get hot and dry, the caterpillars go into hibernation," Sarro said, and the tent won't be needed. The human volunteers water the plants daily and provide honey-tinged water in dishes for the adult butterflies.
Over several years, participants say, enough butterflies might breed so that some can be released around Druid Hill Park in Baltimore and around the state. "We're sort of learning as we go," Sarro said.
