Turneffe Atoll Ecosystems

Coral reefs are the rainforests of the tropical seas filled with vibrant life in a multitude of shapes, sizes and colors. The beauty and complexity of this ecosystem draws tourists to Belize which is important to Belize’s national economy. The reef supports fishermen that use Turneffe as an important fishing area.

Turneffe is considered one of the best developed coral atolls in the Caribbean. It is surrounded by a fringe reef that is well-developed on the east side, with a well-formed fore reef, reef crest and prominent back reef flats. The large, sheltered, relatively shallow inner lagoon supports patch reefs, cayes and extensive mangrove, while beyond the reef crest, the outer slopes of the Atoll fall steeply away into deep water.

Both hard and soft corals are well represented with at least forty-eight of the sixty species of hard corals known to be in Belize identified at Turneffe. Ten of these are considered critically endangered, endangered or vulnerable on the global scale including the reef building staghorn (Acropora cervicornis) and elkhorn (Acropora palmata) corals. The most abundant species encountered are Sea Ginger (Millepora alcicornis), followed by the Yellow Porites (Porites astreoides), Lettuce Coral (Agaricia tenuifolia) and the endangered Boulder Starr Coral (Montastrea annularis).

Even though the reef at Turneffe, where land based impacts are minimal and water clarity is high, is one of the healthier reefs in the Caribbean, the percentage of live coral at Turneffe has declined significantly over the last twenty years. This is a world-wide trend that has been attributed to a multitude of reasons including climate change, over fishing, pollution and siltation from dredging. Since 1998, when Belize experienced a major coral bleaching episode, bleaching events have been recorded at Turneffe Atoll with increasing frequency, likely accentuated by increased acidification resulting from higher CO2 levels in the seas.

Mangroves provide key habitat requirements including shelter, food and nursery areas for a variety of marine species including the commercially important spiny lobster. Extensive mangrove stands cover 62% of the Central Lagoon at Turneffe. The almost unique topography of the Atoll has enabled the deep peaty soils to develop in shallow basins between the sea and the mixed mangrove scrub on its leeward side providing ideal conditions for mangroves to thrive.

Red mangroves (Rhizophora mangle) dominate with their arched roots reaching out into the clear waters providing protection for juvenile fish such as snapper and grouper, and breaking the force of rough waters during storm events to prevent the loss of cayes from erosion.

Black mangrove (Avicennia germinans) and white mangrove (Laguncalaria racemosa) stands are also well represented. They are set slightly back from the waters edge behind the red mangroves. Generally taller, these trees are well adapted to the saline soils and provide structure for nesting and roosting birds including herons, egrets, and osprey. Mangrove thickets also provide habitat for a multitude of smaller animals.

Littoral forest, found only on the cayes and the coastal strand of the mainland, is Belize’s most threatened ecosystem and the most threatened coastal habitat worldwide. This is due largely to coastal development.

A mix of hardy trees and shrubs, the vegetation typically includes both ‘caye forest’ and ‘beach thicket’, with herbaceous ground-cover plants and vines on the upper beach transitioning into woody shrubs with the relatively open canopy of salt-tolerant trees. These forests and scrubs bear the brunt of the storm winds, often showing stunted growth forms in the most exposed locations.

Littoral forest is not only important for resident species, but also for migratory birds that pass through Belize in the Fall and Spring. Belize is a critical transition point for birds crossing the Caribbean Sea, allowing them to rest, feed and refuel before flying on.