Three species of sea turtle, all internationally classified as endangered species, nest on the beaches of St. Christopher (St. Kitts) and Nevis. These are the hawksbill (Eretmochelys imbricata), green (Chelonia mydas), and leatherback or river turtle (Dermochelys coriacea). In addition to seasonal nesting, hawksbills and green turtles of varying sizes can be seen throughout the year feeding in shallow waters. The leatherback is not resident; gravid females arrive each year for a summer nesting season. A fourth species, the loggerhead turtle (Caretta caretta), is occasionally observed offshore.