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Buck Island Reef National Monument

Buck Island Reef National Monument, one of the nation's few underwater parks, combines a barrier island and one of the Caribbean's most beautiful barrier reefs. Part of the Virgin Islands, the 19,000-acre monument, which lies just north of St. Croix, includes 176 acres of land and 18,839 acres of water, offering visitors an opportunity to explore two fascinating worlds.

An underwater snorkeling trail, complete with easy-to-read interpretive signs, meanders through a vibrant coral forest of trees, branches, and spires. Elkhorn coral-patch reefs rise like haystacks as high as 40 feet. Purple sea fans sway lazily in the current, and multicolored sponges cling to the corals. Visitors can swim through this underwater fantasyland accompanied by schools of electric blue and yellow fish and other weird sea creatures. Parrot fish munch on live coral, sea snails creep along the reef, and spiny lobsters hide among the coral, waiting for night to come out to feed.

Many other marine animals thrive in the warm waters of the Caribbean Islands, including three endangered sea turtles: hawksbill, leatherback, and green. The turtles return to Buck Island every two to three years to nest in shoreline forests and on beaches.

In 2001, President Bill Clinton signed legislation that expanded the monument by more than 18,000 acres. The coral barrier reef nearly surrounds Buck Island, a tropical dry forest that is 6,000 feet long and half a mile wide. The island has an impressive variety of plant life, nicely complementing the water's dazzling display of animal life. The species of plants and trees include giant tamarind trees, thorny acacias, and guinea grass.

A nature trail loops along the island's crest, then continues south through frangipani trees, organ-pipe cactus, Ginger Thomas, and bromeliads. A side trail takes visitors to an observation point with splendid views of the coral reef and nearby St. Croix. The island, like the sea, supports a variety of animal life, including endangered brown pelicans, threatened least terns, hummingbirds, and lizards.

How Coral Reefs Work
Living coral reefs are the world's most diverse marine ecosystems. Though they may look like geological formations, the reefs are actually complex colonies of individual animals called polyps. Like underwater construction workers, these tiny animals build the reefs by attaching themselves to the hard skeletons of their predecessors, then producing their own limestone skeletons. The fragile coral structure expands as new polyps constantly grow on the old, their skeletons cemented together by blue-green algae.

Coral reefs, which have existed for millions of years, only grow in tropical waters where sea temperatures are more than 70 degrees year-round. Unfortunately, pollution, overfishing, warming of the seas, boat damage, and other factors are causing coral reefs around the world to disappear.

Buck Island Reef National Monument Information

Address: Christiansted, VI 00820-4611
Telephone: 340/773-1460
Hours of Operation: Open daily, sunrise to sunset
Admission: Free

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To learn more about national monuments, memorials, and historic sites, and other travel destinations in North America, visit:


Eric Peterson is a Denver-based author who has contributed to numerous guidebooks about the Western United States.