Thousands of the purple martins roost at medical center
By Maggie O'Brien
They have been meeting nearly every evening — and some mornings — for more than a week now, a group of anywhere from a few to a dozen or so people who are hooked on bird-watching.
Not just any birds, mind you. As many as 35,000 purple martins, which have made an extraordinary late-summer roost in Omaha.
"It's a purple martin storm," said Justin Rink, a self-described birder who watched, amazed, as the sea of birds with their signature purple-black sheen soared above the Nebraska Medical Center.
A few gutsy martins dived so low that they stopped just short of grazing Rink's baseball cap.
Omaha birder Jim Ducey, who alerted other birders to the flock almost two weeks ago, said about 15,000 birds initially appeared on the hospital campus — a number that he said has more than doubled this week.
This might be the largest purple martin gathering recorded in Nebraska, said Robert Harms, a biologist with the U.S. Fish and Wildlife Service in Grand Island.
"It's unusual to hear about that many," he said. "That's a huge number."
Greg Butcher, director of bird conservation for the National Audubon Society, said it's normal for purple martins to swarm before migrating to South America. What's a little strange, he said, is that such a large flock would congregate in Nebraska. The birds tend to flock together at points farther southeast.
The flock also is notable because since 1980, purple martin populations have declined across the United States, according to the Cornell Lab of Ornithology's "Birds of North America Online."
Scientists don't know what caused the decline, but they say changes in weather or competition from other birds such as house sparrows and European starlings might be factors.
The medical center has had to take steps to minimize purple martin deaths on the campus.
That's because purple martins, like other migrating birds, are protected by federal law under the U.S. Migratory Bird Treaty Act of 1918, which says that they cannot be harmed or killed, even unintentionally, Harms said.
A person or business could face thousands of dollars in fine per bird that is killed. But Mark Webb, a special agent with the Lincoln office of the U.S. Fish and Wildlife Service, said, "Our goal is to conserve wildlife, not to prosecute every potential violator." If there is a problem with birds being killed, Webb said, officials try to work with businesses to address the matter.
Harms said 15 purple martins from this flock are known to have died after crashing into the windows of a skywalk at the medical center.
Paul Baltes, a medical center spokesman, said the grounds staff, upon the advice of federal officials, temporarily covered the windows so the birds would not see reflections of themselves or trees and fly into the glass.
No birds have died since the window coverings went up Saturday morning, and the medical center was not fined.
"We want to do everything we can to make sure the birds are protected," Baltes said.
The purple martins, the largest of the swallow family, roost in about 12 trees on 44th Street, just south of Farnam Street. Their migration route will take them to Florida and other Southern states before they head to South America, where they will spend the winter.
They will return to the Midwest next spring, probably around the end of March or beginning of April.
The purple martins' annual journey seems a little late this year, said Dennis Devine, known as the Purple Martin Man of Council Bluffs. The reason?
"Only God knows why," said Devine, a bird lover for much of his life.
One reason purple martins flock together is to find safety in numbers against predators, such as peregrine falcons. It's easier for purple martins to form large flocks at this time of year because food supplies are plentiful. The birds feast on dragonflies, grasshoppers, mayflies and other insects.
On a recent night, the martins twirled and swooped through the air, flirting with fascinated onlookers, before again rising into the sky — still a deep blue, even at dusk — and darting from tree to tree. They incessantly chattered — although males chortle, Rink said — making their own unique music that is part chirping songbird, part locust. After a half-hour or so, they settled into the trees to rest for the night before taking off around 6 a.m. the next day.
"They really sounded like rain," said Ari Nowacek, a medical student and Ph.D. candidate at University of Nebraska Medical Center, who watched and listened to the birds during a research break. "It's not noise. It's a pretty song."
Added Devine, who was decked out in a purple hat and shirt to honor his feathered friends: "This is better than Christmas."