Trunk Cay

Trunk Cay is one of St. John's most iconic dive and snorkel sites, a small uninhabited island in Trunk Bay whose surrounding reef is famous across the Caribbean for both its beauty and its long-established status as a protected marine environment. The site is within Virgin Islands National Park, and the combination of protection and visibility has made Trunk Cay a reference point for what healthy Caribbean reef diving should look like — a standard against which other sites in the region are implicitly measured. The reef surrounding Trunk Cay is exceptional in its coral diversity and condition. Elkhorn coral formations — historically one of the dominant reef-building species in the Caribbean and now rare on most reefs due to bleaching and disease — are present here in recovering colonies that represent one of the Virgin Islands' most encouraging coral conservation stories. Staghorn thickets provide the complex three-dimensional habitat that juvenile reef fish require, and the schools of young fish that shelter in these formations are a visible indicator of reef recruitment and future health. Fish life around the cay is everything that Virgin Islands National Park protection should produce. Parrotfish of all three species common to the Virgin Islands — stoplight, queen, and rainbow — move through the reef in their various colour phases, their continuous grazing fundamental to the nutrient recycling that maintains reef health. Surgeonfish aggregations sweep across algae patches in coordinated feeding. The french grunt — perhaps the most sonically distinctive fish in the Caribbean — lives up to its name with the grunting sounds audible even through water when the school is large and active. For beginner divers, Trunk Cay provides an experience that captures the essence of Caribbean reef diving in its most complete and accessible form. The snorkelling trail at the adjacent beach has introduced thousands of visitors to the underwater world, and many of them return specifically to dive the deeper sections of the Trunk Cay reef — an extension of the discovery that began in shallower water and reveals the full depth of this extraordinary marine environment.