Mentioned by planetware.com
10 Top-Rated Attractions & Things to Do on Sanibel Island | PlanetWare
"J.N. Ding Darling National Wildlife Refuge is the premier destination in the area for seeing nature and wildlife. The visitor center, open to the public free of charge, is a great spot to learn about the ecosystems and animals, as well as the history of the refuge's founder, Jay Norwood "Ding" Darling. Informative displays, large picture windows, and the latest wildlife spotting information will get you right up to speed on everything nature related on Sanibel."