J.N. “Ding” Darling National Wildlife Refuge is located on Sanibel Island in south Florida. Part of the largest undeveloped mangrove ecosystem in the United States, the refuge is famous for its spectacular migratory birds. One of the most recognizable is the roseate spoonbill, a large pink bird that uses its long, curiously shaped bills to catch prey as it wades in shallow water. Photo courtesy of Harold Wagle.