Shorebirds show a strong affinity for wetlands, and typically swarm the beaches, marshes, and tidal flats during migration. Because large numbers of shorebirds are concentrated in just a few areas during migration, loss or degradation of key sites could devastate these populations. Delaware Bay, at the southern end of the New York Bight, is the largest spring shorebird staging area on the east coast of the United States, and one of the top ten sites in the Western Hemisphere. This site is recognized as globally important in the Western Hemisphere Shorebird Reserve Network. Shorebirds migrate through the Northeast almost all year round, with northward migration beginning in late winter and lasting through June, and southward migration beginning in late June with peaks in late July and lasting into the fall.
Shorebirds rely on a mosaic of shallow coastal or freshwater wetlands and adjacent upland areas.
Foraging habitats include beaches, mudflats, sandflats, salt marshes, impoundments, flooded agricultural fields, and grasslands. In coastal areas, preferred food items include macroinvertebrates such as polychaete worms, crustaceans, mollusks, or insects. Roosting habitats, usually used at night or during high tide periods when primary feeding areas are not accessible, include salt marshes, sandflats and beaches above the tide line, and sparsely vegetated islands free of predators. The greatest threats to migrating shorebirds are loss and degradation of coastal habitats, loss of food resources, and human disturbance.