The Daniel Webster Wildlife Sanctuary has historically been home to a large colony of purple martins. And, because the sanctuary is one of the last remaining managed cultural grasslands in Massachusetts, species that rely on such habitats breed there in the spring and summer, most notably bobolinks. Mute swans and several species of ducks and geese feed on the pond. Ducks, geese, herons, egrets and a wide variety of shorebirds visit the wet panne, while several species of birds of prey, most notably red-tailed hawks and northern harriers, feed on the small rodents that breed in the grasslands. Several species of owls have historically roosted in the red maple swamps during the winter, including great horned, barred, long-eared, short-eared, eastern screech and saw-whet owls. The sanctuary's plants provide ample food for warblers, sparrows and many other species during migration.