By Lynford Simpson, Staff Reporter 
Land and Environment Minister, Horace Dalley.
A report tabled by Dalley found that "where there was a dominance of coral, algae now almost cover the reefs."
A MIX of natural and man-made disasters has wreaked havoc on much of the coral cover on the island's north and northwest coasts, according to the report on the environment which was tabled in Parliament by Land and Environment Minister Horace Dalley.
The report found that during the last 20 years there have been dramatic changes on the fringing reefs around the island. During this time, mean coral cover at 10-metre depth fell from 52 per cent in the late 1970s to three per cent in the early 1990s.
"Where there was a dominance of coral, algae now almost cover the reefs. Deeper reefs are in comparatively better condition, particularly on the southern shelf edge," the report said.
According to the report, major causes for the deterioration are: coral diseases (particularly white band disease); hurricanes Allen (1980) and Gilbert (1988); and the loss of herbivores through extreme over-fishing.
It added that sewage pollution has played a role at many sites, and said coral bleaching from temperature increase in the ocean was most severe in 1995, but not as much in the 1998 and 1999 episodes. It said "corals are also sensitive to siltation and excess of nutrients, both of which occur at river mouths."
An Atlantic and Gulf of Mexico Rapid Reef Assessment (AGRRA) study done in 2000 which covered the entire north coast found that coral reef mortality in the shallow water was very high.
In some instances mortality level was as high as 80 per cent. The nutrient rich water, due to the absence of herbivores such as parrot fish, surgeon fish and the long-spined urchin, caused a 92 per cent increase in the algae cover as the densities of these herbivores are inadequate to eliminate the large amount of algae. In addition, along the coast from Ocho Rios to Falmouth the high levels of algae growth are also aided by an upstream source of nutrient input.
The report noted that the conditions of the reef have been of major concern. One step taken to help resuscitate the coral reef is the introduction of marine parks.
These marine parks will prevent over-fishing, thus giving the fish life and urchins a chance to complete their growth cycle. If this happens the algae growth will be reduced since the densities of the herbivores would have increased. So far there have been some positive signs in the re-growth of coral reef, although the process is very slow.
