Protecting the Threatened and Endangered: Sanibel Island

What began as a sandbar is now Sanibel, a barrier island fringed with mangrove trees, shallow bays, and white sandy beaches located off the southwest coast of Florida.



Jay Norwood Darling, a nationally syndicated editorial cartoonist, 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 Wilderness Area. Protecting endangered and threatened species has always been an important aspect of Ding Darling Preserve's mission.


There are several species of turtles on Sanibel that are considered threatened or endangered. The loggerhead turtle is the most abundant form among Florida's sea turtles. It is the only species which regularly nests in substantial numbers on the beaches of Sanibel and Captiva Islands. The loggerhead is considered to be a threatened species.



The rarest and smallest of the sea turtles, the Kemp's ridley, occurs in the region year-round.

This declining species primarily congregates for mass nesting on the Mexican Gulf coast north of Vera Cruz. In the last two decades individual ridleys have nested in Florida, including a documented nesting on Sanibel Island. Because of its drastically reduced population the Kemp's ridley is considered endangered throughout its range.

The leatherback turtle feeds almost exclusively on pelagic jellyfish. This species is a very rare visitor to the barrier island beaches of Southwest Florida, and there are no recent records for the species here. Leatherbacks are infrequently observed offshore. The leatherback is listed as an endangered species.

Juvenile hawksbill turtles are the most rare of all the world's marine turtles. Through time the shell of this species has been highly valued because it is the source of tortoise shell. Because of exploitations, the collection of the shell is no longer sanctioned by most countries in the Americas. Japan, however, continues to import tons of the product from around the globe----from wherever tortoise shell is still harvested in Third World countries. Adult hawksbills resemble loggerheads and it sometimes takes an expert to distinguish them apart in the limited areas where they may utilize the same nesting habitat. The hawksbill is primarily a creature of reefs and hard bottoms where it feeds on coral polyps and sponges. The hawksbill is considered an endangered species.