Horace DalleyTHE REMAINING mangroves which are found mainly in the Portland Bight area, are "under pressure" according to the report on the environment recently tabled in Parliament by Horace Dalley, Land and Environment Minister.
It lists "the desire" to use the coast for other purposes (settlements, tourism) as well as the many uses of mangrove, including charcoal making and construction material, as the main reasons why mangroves are threatened.
Portland Bight is a protected area that covers 724 square miles of land and sea from the Hellshire hills in St. Catherine to Rocky Point, Clarendon.
According to the report, infrastructure developments and buildings "threaten the wetlands, both directly and indirectly". This occurs, in some instances, when the course of water is changed, by the dumping of waste and other activities.
However, data on the impact on wetlands are scarce. Although the land use data show no reduction in wetland area as such, and only 0.2 per cent loss of mangrove area over the period 1989-1998, these data do not reflect the state of the wetlands, the report cautioned.
Mangroves are found in saline and brackish water. The most common species in Jamaica are the red and black mangrove, but there is also white mangrove and button-wood. Mangrove forests occur along much of the south coast and in isolated strands along the north coast.
The most extensive remaining stands are found in the Portland Bight area, which is now a protected area. The mangroves in Jamaica are found along 290 km, or 29 per cent of the coastline. The area covered by mangroves is 97 km. This area has remained constant over the last 10 years.
Mangroves form the basis of a complex marine food chain. They constitute a breeding habitat for many species, including worms, snails, shrimp, molluscs, mussels, clams, oysters and some fish, offering protection for maturing offspring.
Mangroves filter and assimilate pollutants in runoff, improving water quality. They stabilise bottom sediments and protect shorelines from erosion and other effects of strong winds and waves.
