Shoreline erosion, invasive reeds, oil spills, farming, and human and animal activity at popular beaches all threaten nesting and foraging habitat for migratory birds on this major migration route. While much of this region is protected, remaining areas are increasingly threatened by urban sprawl.
For more than a million neotropical birds, migrating every spring from South America to Canada, the Delaware Bayshores beckons like a big Holiday Inn. Special buffet tonight: tiny green horseshoe crab eggs, freshly laid and served right on the beach! Every May and June the birds feast greedily, doubling their weight before heading on to higher latitudes.
But now this great migratory rest stop along the Atlantic Flyway is in trouble. Once it held one of the country’s greatest oyster beds; ravaged in the 1950s and 1990s by parasites, the bay’s oyster population is still in critical condition. Horseshoe crabs, more abundant here than anywhere else in the U.S., have been so drastically overharvested that migrating birds dependent on their eggs (most notably the endangered red knot) are dying off. The recent arrival of the alien Chinese mitten crab threatens to push out what’s left of the crabs. Residential development around the bay reduces habitat and pollutes the water. And then there’s climate change, with milder winters and rising sea levels throwing traditional migratory patterns out of whack.
Lying between the Delmarva Peninsula (“del” for Delaware, “mar” for Maryland, “va” for Virginia) and New Jersey’s southern shore, Delaware Bay is not as big as its neighbor, Chesapeake Bay, but it’s the culmination of a vast watershed that runs upstream through Pennsylvania to Hancock, New York , the longest undammed main-stem river east of the Mississippi (and spawning grounds for species such as the American eel, American shad, Atlantic sturgeon, and shortnose sturgeon). This great interdependent water system doesn’t care where state boundaries fall. But thanks to coordination by the U.S. Fish and Wildlife Service, the Nature Conservancy, and local Audubon society chapters, a patchwork of local parks preserves as much of this landscape as possible—not an easy task in this thickly settled Northeast corridor.
A mile from Philadelphia International Airport lies the shimmering tidal marsh of the John Heinz National Wildlife Refuge, 8601 Lindbergh Blvd., Philadelphia. Two major wildlife refuges in Delaware State are at Bombay Hook, 2591 Whitehall Neck Rd., Smyrna, whose tidal salt marshes are prime nesting grounds for wood ducks, bluebirds, purple martins, barn owls, and eastern screech owls; and 10,000-acre (4,046-hectare) Prime Hook, 11978 Turkle Pond Rd., Milton, with its wide mix of woodland and wetland habitats where bald eagles nest, peregrine falcons stop over, and the endangered Delmarva fox squirrel makes its last stand. Also, check out the New Jersey Audubon Society’s online guide to popular birdwatching sites in the state’s marshlands, forests, and beaches, including Cape May.