A flight of eight Canada geese curves down and hovers almost motionless over the mud flat, wings spread wide in the breeze blowing fresh off the Blackwater River.
The birds stretch out as sleek and elegant and streamlined as Navy Tomcats approaching the deck of an aircraft carrier. Then they drop their legs and with a last flurry of beating wings land gently among the geese already feeding in the mud and tawny marsh grasses of Blackwater National Wildlife Refuge.
They've probably flown a whole lot farther than most Tomcat jets ever get from their flight decks. These geese are part of the fal migration, which is just now reaching its peak. Birds of the Mid-Atlantic Canada goose population commonly fly 1,500 miles from their breeding grounds on Ungava peninsula east of Hudson Bay in Canada.
Maryland's Eastern Shore, of course, has always been smack in the middle of the eastern flyway, but more and more it is the destination of the V-shaped flights of geese honking across the thin blue autumn skies, or silhouetted against the harvest moon.
And more and more Canada geese winter at Blackwater, as many as 30,000 to 40,000 each year. The refuge sprawls over 16,670 acres of the marshes of the Blackwater and Little Blackwater rivers in the center of Dorchester County.
Glenn Carowan, the manager at Blackwater, grew up at Lake Mattamuskeet in North Carolina and worked part time at the refuge there when he was a teen-ager. As many as 100,000 Canada geese once wintered at Lake Mattamuskeet. Now only 15,000 or so do. Thousands once wintered in Florida. Now none do. Most of them now "short-stop" on the Delmarva Peninsula.
Carowan's an outdoorsy kind of guy with a ruddy complexion, windblown red-blond hair and a bristly red-blond mustache. He's been in the Fish and Wildlife Service since he was 20. He's 40 now and has worked at 23 refuges in eight states. He's very enthusiastic about Blackwater and knowledgeable about his job.
"We've got a variety of habitats here at Blackwater," Carowan says. "Open marsh, open water, brackish marsh, freshwater marsh, marginal timber uplands, mixed mature hardwood and pine forests. We've got palustrine forested wetland, sweet gum, maple, willow oak, water oak, predominantly hardwoods."
The flight of eight Canada geese landed in a 30-acre moist-soil impoundment, Pool 1 on Wildlife Drive, the visitors' route through Blackwater.
Padding around in the mud, the geese lose most of their sleekness and tend to look like stout Dutch burghers waddling around 14th century Holland.
"We have about 400 acres of moist-soil impoundments," Carowan says. "We manipulate the water level up and down. We take the water off in June and let the rain fill them up in the fall."
The pools need a little rain to reach the preferred level for this time of year. And rain comes in later in the day on the 20-mile-an-hour wind blowing in from the river.
"By managing the water levels we can almost predict the vegetation we'll get," Carowan says. He points out red-root cyperus, panicum, Walters millet, all of which waterfowl find tasty, for the leaves or seeds.
"When the birds come this time of the year, we'll close the water gates and it'll flood all the plants, which produces an abundance of feed. We flood in stages. When we get two or three inches of water, the ducks just go crazy. We'll have 15,000 ducks right here."
The refuge plants four or five hundred acres of agricultural fields for waterfowl, Carowan says, a little farther along on Wildlife Drive.
"We try to plant crops that meet the seasonal needs of the wildfowl. Right now they need to replace protein lost in migration. In colder weather they need carbohydrates to maintain body temperature.
"That stuff out there where the geese are eating is white clover," he says. "They eat the little white flower and all the leaves.
"This time of year geese are grazers. They won't even touch corn, or milo, or soybeans until the weather gets cold. That's like you setting down to eat a plate of spaghetti.
"When it's warm like this they like eating salads. They turn to green browse: winter wheat, rye grass or your clovers."
L The geese prefer white clover to crimson and crimson to red.
"I tried it," Carowan says. "There's a difference. The white clover is sweeter and it's stringier."
The mixed forests of hardwoods and loblolly pine at Blackwater are the habitat of the Delmarva squirrel, a species native to the Eastern Shore and endangered.
"We've got one of the largest populations on the Shore," Carowan says. "What we try to maintain is a parklike understory, not a lot of undergrowth. We thin from underneath. We want a mature forest. Delmarvas like that."
The staff manages the deer population at Blackwater to manage the woodland.
"We want a real high deer herd here," Carowan says. "They do the thinning of the understory for us. Because they're browsers they eat twigs and leaves and your vegetation coming up. They keep the parklike atmosphere.