An Island Reborn
By Fariss Samarrai
Photos by Dan Addison
|Mike Ewin examines a common tern egg to determine its hatching date. As the embryo develops, a gas bladder inside the egg expands, and the egg floats higher in the water.
Bird expert Mike Erwin helps restore habitat
Mike Erwin points to a flock of least terns rising in a panic from their nesting site on a man-made shell mound beyond a mudflat. The birds flutter about on sleek wings making startled calls, alerting each other of some present danger.
“See that? This is the second time they’ve risen like that in 10 minutes,” Erwin says. “It might be a fox moving around in there.”
From this distance he can’t see a fox or whatever is startling the birds, but this disruption of the site does not bode well for the successful hatching of the hundreds of tiny eggs laid in small nests scattered among the weedy shell mound. If the birds are disturbed too often they will abandon their nests and the hatching will fail.
In most places, a fox hunting within a nesting colony is an accepted routine of nature taking its course. But here on Poplar Island, an oasis in the middle of the Chesapeake Bay, humans are, in effect, altering nature’s course. But in the process, creating an island habitat that is highly conducive to the successful breeding of an assortment of threatened birds, as well as diamondback terrapins.
Poplar is an island once diminished and now reborn. It is a work in progress — both an active construction site and a living laboratory where wildlife biologists are establishing habitat designed to encourage nesting. Along the way, they learn what works and what doesn’t while trying to attract specific birds to nest or feed and roost during migration in spring and fall. More than 100 species of shore and migratory birds have been recorded on the island, including osprey, least and common terns, bald eagles, egrets, ducks, geese and swans, cormorants and — always — plenty of gulls. Many species are actively nesting in this sanctuary.
And that is why Erwin is here. He is a bird expert with joint appointments with U.Va.’s Department of Environmental Sciences and the U.S. Geological Survey. Erwin’s job on Poplar Island is to help engineers design a wetland bird habitat that will encourage nesting. During the spring and summer nesting seasons, Erwin visits Poplar about once a week to conduct nest and population surveys and to meet with engineers and biologists from the U.S. Fish and Wildlife Service to discuss strategies for optimizing nesting conditions. Erwin is attempting to create ideal conditions for terns and other threatened birds, while discouraging the nesting of gulls and other common species that prey on the eggs of the threatened species.
For centuries, Poplar Island was a 1,000-plus-acre, crescent-shaped wedge of land in the bay. It was home to abundant populations of wildlife. Native Americans hunted and fished there. Then, European settlers discovered the island and settled there. For more than 300 years the island was home to a thriving farming and fishing community. In the 1930s, it was a popular hideaway for prominent Democrats, including Franklin Delano Roosevelt, who often visited a resort there to fish with his political pals.
But the island was slowly eroding away. Through a combination of rising seas, sinking land, storms, wind, tide and human activity, the sands were shifting and Poplar was disappearing. During a 150-year period, the rising bay slowly breached the island. By the early 20th century, Poplar had broken into three small islands. Slowly, families there realized that the life they had built was washing away. One by one, they packed up and moved to the mainland. By the 1950s nobody lived on Poplar Island.
REBUILDING THE ISLAND
But what remained of Poplar presented an opportunity. Each year the bay’s shipping channels must be dredged to accommodate the huge freighters and tankers traveling to and from Baltimore. Something must be done with the millions of tons of sediment dredged up from the bay bottom.
And there lies Poplar Island.
Through a project sponsored by the Baltimore District of the Army Corps of Engineers and the Maryland Port Administration, dredge material is transported to Poplar Island and is being laid in approximately the original “footprint” of the island. This is a 20-year, $394 million project designed to turn Poplar Island into a 1,110-acre wildlife refuge. Already a 550-acre extension is being planned even before the Poplar work is completed.
Poplar Island is being designed as a labyrinth of external jetties and dikes and internal cross dikes, dividing the island into a series of cells, each structured to encourage nesting and visiting by birds, turtles, butterflies and a host of wetland plants, fish and other species. The shallow mudflats and marshes also serve as nurseries for fish, crabs and other marine life. When completed in 2014, half of the island will be upland habitat facing the open bay and half will be protected marshland on the backside of the island.
Reconstruction of Poplar Island began in 1998; the project is the largest of its type. When finished, 38 million cubic yards of sand and mud will have been used to rebuild the island, the equivalent of 3.3 million truckloads of dirt. The island will then be preserved as a nearly undisturbed state or federal wildlife preserve.
WORSE THaN A FOX IN A HEN HOUSE
But at the moment, Erwin is concerned about the fox. So far, since spring 2004, four foxes have been trapped and removed from Poplar Island. The foxes apparently are swimming there from a small adjacent island that once was a part of the original Poplar Island. The animals regularly feed on bird and turtle eggs, and at least one of them has so far eluded the biologists. It’s a real problem for the tern population. These birds are experiencing poor hatching rates despite the fact that Poplar Island is the only place on the Chesapeake Bay where they are nesting. Last year, more than 800 pairs of common tern nests failed to produce any young. This year, numbers of nesting birds are down, but some are at least hatching, an improvement over last year. “We’ve got to catch that crafty fox,” Erwin says.
A THRIVING HABITAT
But most of the other bird populations are doing well, and more species are establishing nesting sites each year as new habitat is constructed. Cormorants, for example, are proliferating, with about 760 nests on the island this year.
And on this day, a group of volunteers from the National Aquarium in Baltimore are planting more than 25,000 plugs of two types of Spartina — salt marsh grasses — on a six-acre section of mudflat in a recently constructed cell. It’s muddy, labor-intensive work and right now the plantings look sparse. But in a few years, as the dikes are opened, allowing tidal waters to ebb and flow, the section will look as natural as many shore areas along the bay. Eventually Erwin will have plenty of birds and their nests to count here too.
“This island serves as a bird magnet,” he says. “The birds fly down the bay looking for a place to nest or stop, and here it is — a wetland oasis in the middle of the broad open Chesapeake.”
On an island reborn.