Disturbance and Recovery of Sooty Tern Nesting Colony in Dry Tortugas National Park

The sooty tern (Onychoprion fuscatus), an abundant pelagic seabird common throughout tropical waters, is an important ecological indicator for the health of the world’s oceans due to its widespread distribution and long life history. The nesting colony on Bush Key, Dry Tortugas National Park has been the subject of a 16-year monitoring effort to track changes in nesting population and plant community present on the island. A devastating hurricane season in 2005 reduced available nesting habitat by over 70%. By 2013, available habitat had recovered to 92% of pre-disturbance levels. Recovery of nesting pairs continues to lag with an estimated 16,000 in 2016, compared to 40,000 in 2001. Plant community composition remains significantly altered. This analysis is vital to park managers charged with protecting the natural resources of our National Parks. Continued monitoring will be necessary to assess emerging threats to marine resources, such as climate change and increased anthropogenic pressures.