The park's coral and sea grass communities are among the most vibrant in the Florida Keys. Hosting myriad species of colorful corals and reef fishes, these watery wonderlands entice exploration by intrepid snorkelers. Visitors who prefer to stay dry have the opportunity to observe other wildlife, including nearly 300 species of birds, the majority of which are migratory. The sooty tern finds its only regular nesting site in the United States on Bush Key, adjacent to Fort Jefferson. Large sea turtles lumber onto the park's protected beaches each summer to bury their clutches of eggs. These and other wonders make this park a truly one-of-a-kind destination for wildlife viewing.