Buck Island off the south coast of St. Thomas is a small, uninhabited cay that has become one of the island's top snorkel stops. The surrounding water is shallow, clear and protected, with seagrass beds that attract green sea turtles and rocky patches where reef fish gather. A typical half-day trip is a catamaran sail from Frenchman's Reef or a nearby marina to the cay, with time to snorkel, swim and often a beach stop on neighboring sand. Because the sailing leg is short and the snorkeling is easy, it suits first-timers and families as well as experienced swimmers. Guides supply equipment, lead the group to spots where turtles feed and keep an eye on the swimmers. This is the St. Thomas Buck Island, not the national monument of the same name near St. Croix, which is a separate island and a different excursion. The trip fits neatly into a morning or afternoon schedule, leaving the rest of the day free.
What makes this outing popular is its reliability. Turtles are never guaranteed, but they graze in these grass beds regularly, and the shallow depth means you can often watch them from the surface without diving down. Reef fish such as parrotfish, sergeant majors and wrasse are common around the rocks, and rays or small barracuda sometimes appear.
Snorkeling here is gentle
The water is warm, the currents are mild on most days and the guide helps newer swimmers find their rhythm. Life vests, noodles and extra instruction are typically available, so non-swimmers and nervous children can take part at their own pace.
The sail itself is part of the pleasure. A modern catamaran provides stable decks, shade and a smooth ride, and the views of the south coast, with its mix of resorts, hillside villas and open sea, are a good introduction to the island's geography. Many operators serve water, soft drinks or light refreshments, and some offer rum punch on the return leg.
If a beach stop is included, it is usually a short swim or wade ashore for a stroll and a break. As you plan, check the details: whether lunch or drinks are included, whether alcohol is served, the age limits for children and whether the operator uses mooring buoys to protect the seagrass and coral.
Be a good guest of the turtles. Keep your distance, never chase, touch or feed them, and give them room to surface for air. Wear reef-safe sunscreen or a rash guard to protect both your skin and the water. Bring a towel, a hat, sunglasses and a dry change of clothes, and take a seasickness remedy if you are prone to motion sickness. Conditions can change with wind and swell, and captains will modify the route for safety, so treat the plan as flexible.
Book ahead in the busy season, especially for morning departures, and confirm the departure point because boats may leave from different marinas. If you are choosing between several snorkel trips, this one stands out for its short travel time, its easy conditions and its good odds of a memorable turtle encounter, and it pairs well with a sunset sail on another evening.
What to expect
The experience
A guided catamaran trip from the south coast to Buck Island with a snorkel session in turtle-grazing seagrass and a swim or beach stop.
Best time
Morning departures for the calmest water and best visibility.
How long
Three to four hours door to door.
Tips
Apply reef-safe sunscreen, bring a towel and a seasickness remedy and keep a respectful distance from turtles.
Quick picks
- Best for
- First-time snorkelers, families and anyone who wants a turtle encounter without a long boat ride.
- Families
- Children who can swim or use a vest enjoy it; check minimum age rules.
- Couples
- A relaxed sail with easy snorkeling and a refreshing drink on the way back.
- Pair with
- A sunset sail or a Mountain Top drive on another day.
- Time needed
- Three to four hours.
Good questions
Is this the same Buck Island as the one near St. Croix?+
No. This is a small cay off St. Thomas's south coast, separate from the national monument near St. Croix.
Will I definitely see turtles?+
Turtles are common but not guaranteed. Fish and reef life are reliable.
Can beginners join?+
Yes. Equipment, instruction and flotation devices are normally provided.
Are drinks included?+
Many trips include water and soft drinks, and some offer rum punch. Check your booking.
What if the weather is poor?+
Operators may change the route or reschedule for safety. Check their policy when you book.