Northern exposure favored

Environment: Scientists welcome the arrival of brown pelicans on a Chesapeake Bay island, now the nation's northernmost nesting colony of these birds.

July 05, 2002|By Stephen Kiehl | Stephen Kiehl,SUN STAFF

BARREN ISLAND - The baby pelicans hatching here this summer are beastly things, with featherless purple bodies and fleshy pouches that quiver under their beaks.

They would resemble lizards, if they weren't so ugly.

But in the eyes of wildlife ecologist Dave Brinker, they're a beautiful and welcome addition to the Chesapeake Bay - an encouraging sign that the bay's ecosystem is strong enough to attract more species.

Spring marked the first time that the once-endangered brown pelicans nested on this spit of sand and scrub in the bay southwest of Cambridge. It is the northernmost brown-pelican nesting colony in the nation, biologists say.

"They're filling a niche here that hasn't been filled for a long time," said Brinker, who works for the state Department of Natural Resources and has tracked the significant growth of pelicans during the past few years

Pelicans are strong, big-bodied birds with prehistoric-looking pouches used to scoop up fish. They're popular among fishermen and bird-lovers for their distinctive features and graceful flight.

One morning this week, Brinker and two assistants tagged 11 baby pelicans on this aptly named island. Tiny and muddy and sparsely covered by salt marsh cordgrass, the island has been left to the birds. Even mosquitoes don't bother with it.

The pelicans Brinker wanted were 4 to 5 weeks old and had outgrown their gawky stage. They were covered with tufts of white feathers and perched on sprawling nests of brittle wood.

"Hi, guys!" Brinker called as he approached three of them. "Now don't go taking off like that."

One started wobbling away. A braver one spread its wings and stepped toward Brinker. It squawked and snapped its long beak.

Brinker, who has scrapes on his arms and legs because some pelicans got a piece of him in recent weeks, was unfazed. With his hand around its beak, he picked up the bird and cradled it to his chest like a baby. It promptly regurgitated a half-digested fish - another defensive maneuver.

DNR technician Stacy Wolff snapped a metal band around one of the bird's legs, using pliers to line up the seams. The band had the equivalent of a pelican Social Security number and a telephone number for people to call if they find the bird.

Then Gwen Brewer, a DNR scientist, wrapped a blue plastic band around the bird's other leg. This band, with a letter and number, is visible to bird-watchers and indicates the year and location in which the bird was banded.

Pelicans banded in Maryland have been found as far north as Maine and as far south as Cuba. The bands help scientists track the birds' life expectancy, migration and breeding habits. The state DNR has banded 3,400 baby pelicans in the past two years and an additional 900 this year.

Most of Maryland's pelicans are found at the mouth of the bay. Smith Island has 1,000 pairs this year, according to a recent DNR census - double the number noted a year ago. All told, about 7,500 pelicans have made the bay their home this year.

"It's a very hopeful sign that the Chesapeake Bay has what it takes to support them," said Katharine Parsons, a senior scientist and predatory bird expert at the Manomet Center for Conservation Sciences in Massachusetts. "There has to be enough of a food base for them to not only sustain their own lives but also to raise their young."

Pelicans are called colonial nesting birds because they nest in large, dense groups - creating a colony on a barren island. They prefer such places because they build their nests just off the ground, often on top of shrubs - places that are vulnerable to predators.

Three decades ago, the pelicans' biggest threat was manmade. The pesticide DDT caused their eggshells to thin and break, and the pelican population reached perilously low numbers. After DDT and some other chemicals were banned in the 1970s, the birds made a comeback. Along Texas' Gulf Coast, for example, the number of nesting pairs of pelicans has increased from six to 3,400 since 1973, according to the U.S. Fish and Wildlife Service.

"They're a flagship success story," Parsons said, noting the large pelican populations in the Southeast and along the Gulf of Mexico coast. Some colonies in Florida are so numerous and friendly that the birds have become panhandlers, she said, begging tourists for food.

Brinker said the Chesapeake Bay's health isn't the only reason the dun-colored birds have returned to Maryland. The gradually warming climate has become hospitable for the pelicans, which need a long warm season to raise their young. Babies can't fly until they're about 9 weeks old and are dependent on their parents for up to 13 weeks.

Also, the surging pelican population in the South is pushing some of the birds farther north. Some Maryland colonies, Brinker said, have greater reproductive success than those in Florida.

"In some places, they're at the limits of what the fishery resources will allow," he said. "These birds are looking for good places to breed."

He's thrilled that Barren Island is one of those places. The birds are on one of Barren Island's satellites - a narrow strip of sand barely above water. It was created by the erosion of Barren Island, and this season is home to several hundred pelicans.

Brinker counted 51 nests when he went out this week, up from 17 a month ago. After banding the chicks, Brinker and his assistants got back in their 12-foot-long boat and motored away. The adult pelicans that had been circling overhead, keeping a wary eye on the humans, returned to their babies.

"They're saying, `Whoa, what are those new bracelets you've got?'" said Brewer, the DNR scientist.

"A lot of the parents," Brinker added, "have the same ones."

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