Status of Coral Reefs of the World 2000

Status of Coral Reefs of the World: 2000
most recently Hurricanes Jose and Lenny in late 1999, caused severe damage to dive sites
at Norman Island, Peter Island, Salt Island, Cooper Island, Ginger Island and Virgin Gorda.
Barbados
Quantitative surveys have been conducted since 1982, initially on the west coast, with the
south and east coasts included in 1987. West coast fringing reefs are considered to be in
poor condition and patch reefs on the southwest coast deteriorated significantly during the
study period. From initial surveys of the Atlantic coast it appears that reefs are generally in
good condition with high faunal diversity.
The French Caribbean
Mapping using remote sensing revealed that only 15 to 20% of the marine communities of
Martinique and Guadeloupe still have flourishing coral communities. Coral cover on
Guadeloupe varied between 14% on reef flats, to 45% on outer slopes. On one site on
Pigeon Island, coral cover dropped from 46% in 1995 to 26% in 1999, and equally
worrying, are the large numbers of partially diseased colonies among survivors varying from
11 to 56%, with an average 19 to 53% of surfaces being dead. There is similar degradation
of the coral communities on Martinique Island. These losses are probably due to a
combination of both natural and anthropogenic factors:
• Hurricanes: These develop in the north tropical Atlantic from July to October, and
Martinique has been damaged by hurricane swells of David (in 1979) and Allen (in
1980), but there have been no recent impacts. In 1989, Guadeloupe suffered from
hurricane Hugo. In 1995, Hurricanes Luis and Marilyn crossed Saint-Barthélémy and
Saint-Martin and also caused damage in Guadeloupe and waves from Hurricane
Lenny in 1999 smashed up on the Caribbean coast of Guadeloupe;
• Diadema antillarum Disease: The loss of the sea urchins in 1983 is still evident as
over growth of algae, however urchin populations are now recovering;
• Coral bleaching: There was major bleaching in 1998, when seawater temperature
exceeded 29°C during September and October. Most hard corals, anemones,
zoanthids and symbiotic octocorals were affected. On Martinique, 59% of the
coral colonies were affected with an average of 69% of the surface bleached. In
Guadeloupe, the impact was similar (56 % of the colonies affected with 80% of
bleached surface). However subsequent mortality of corals was relatively low
with 20 to 30% of the bleached colonies dead in 1999, except for the coral
Diploria labyrinthiformis, which had 80% mortality. There was new bleaching on
the reefs of Guadeloupe in September 1999, affecting 50% of the corals, but the
effects were magnified when Hurricane Lenny passed close by in November;
• Heavy siltation: The reefs receive large quantities of sediment from deforestation,
mangrove clearing and poorly planned development, particularly affecting reefs
in enclosed bays;
• Pollution: Measurement of pollution concentrations is minimal with the only
assessments in the Bay of Fort-de-France. Heavy metals and pesticides have been
found in the sediments and animals, and the importation of 1,500 to 2,000 metric tons
of pesticides per year into Martinique and Guadeloupe potentially threatens their
coastal ecosystems. Wastewater treatment is largely ineffectual and organic pollution
from the growing human populations is a major threat to the coral communities.
320