Loggerhead Key existed on the island in the early 1900s. Fauna of Loggerhead Key includes sea turtles, which are monitored by park rangers with the Dry Tortugas National Park to document nesting and hatching rates. The loggerhead sea turtle is also present on the island. In August 2016, a National Park marine biologist stated that 113 loggerhead turtle nests existed on the island at that time. This was the highest recorded nest rate compared previous years. The island also has brown pelicans. In 1972, hundreds of rhesus macaque monkeys were brought from India to Loggerhead Key by Charles River Laboratories. This was
Loggerhead Key done to provide the monkeys a place to breed, to supply the animals for medical research laboratory experiments. Around 1,322 of the monkeys existed on the island between 1987–1990. The Dry Tortugas Light is a lighthouse located on Loggerhead Key. It began operations in 1858 and was decommissioned in 2014. The Carnegie Marine Biological Laboratory, also referred to as the Tortugas Laboratory, was a marine biology laboratory and research facility constructed on the northern end of Loggerhead Key that operated from 1904 to 1939. It was constructed and operated by the Carnegie Institution of Washington. The Carnegie Marine Biological Laboratory