Small rocky cays, with some sandy beaches, especially at Big Sand Cay. Long Cay is Statutory Sanctuary 25. Other small cays near Grand Turk constitute Grand Turk Cays Land and Sea National Park (Statutory NP 7). Penniston Cay and East (formerly Pinzon) Cay need transferring from this to Sanctuary status; Gibbs Cay should remain a National Park. Big Sand Cay Sanctuary is Statutory Sanctuary 23.
The site qualifies for A4iii status since it is known to hold on a regular basis more than 20,000 waterbirds. East (or Pinzon) Cay supports a regionally important breeding proportion of Audubon's Shearwaters. They probably breed on other Cays as well as East. Laughing Gull (150 breeding pairs) and White-tailed Tropicbirds (40 breeding pairs) are also recorded. Penniston Cay supports internationally important breeding numbers of Bridled Terns, with smaller numbers on other cays. Penniston Cay supports also the only breeding colony of Brown Boobies in TCI and a small colony of Magnificent Frigatebirds, which may reach Caribbean importance in some years. Long Cay supports important numbers of the Caribbean population of breeding Brown Noddies (7,400 breeding pairs) with the numbers here and on Penniston Cay constituting respectively "43%" and "9%" of the Caribbean population. Big Sand Cay's breeding Sooty Terns comprise more than 1% of the global population.
Non-bird biodiversity: Some cays are important for endemic vegetation and lizards Turks & Caicos Rock Iguanas Cyclura carinata carinata and Curly Tail Leiocephalus psammodromus, Shores are likely to be nest-sites for turtles Chelonia midas (EN), Eretmochelys imbricata (CR), Caretta caretta (EN).
BirdLife International (2019) Important Bird Areas factsheet: Turks Bank Seabird Cays. Downloaded from http://www.birdlife.org on 16/10/2019.