Jay Norwood Darling was instrumental in the effort to block the sale of a parcel of environmentally valuable land to developers on Sanibel Island. At Darling's urging, President Harry S. Truman signed an Executive Order creating the Sanibel National Wildlife Refuge in 1945.
The refuge was renamed in 1967 in honor of the pioneer conservationist. The refuge consists of over 6,400 acres of mangrove forest, submerged seagrass beds, cordgrass marshes, and West Indian hardwood hammocks. Approximately 2,800 acres of the refuge are designated by Congress as a Federal Wilderness Area.
The refuge was created to safeguard and enhance the pristine wildlife habitat of Sanibel Island, to protect endangered and threatened species, and to provide feeding, nesting, and roosting areas for migratory birds. Today, the refuge provides important habitat to over 245 species of birds.