Patterns of natural and anthropogenic disturbance of the mangroves on the Pacific Island of Kosrae

Mangroves in many parts of the world are subjected to frequent, large-scale disturbances. A possible exception is Kosrae, Federated States of Micronesia (FSM), a small volcanic island in the west-central Pacific Ocean. Relative sea level has been stable for most of the last 1000 years and the last tropical cyclone to affect the island was in 1905. Many trees on Kosrae, especially individuals of the species Sonneratia alba, therefore appear to die only after reaching advanced ages and exceptional sizes. The most widespread anthropogenic disturbance is harvesting of trees for fuelwood and poles, which is done selectively and generally creates small, dispersed gaps. Other forms of anthropogenic disturbance, such as modifications of coastal landforms, alterations of freshwater inflows, road construction, and conversion to residential or agricultural uses are still relatively minor but have led to some irreversible losses. The economy of Kosrae is based to a large degree on income derived from a Compact of Free Association between the FSM and the United States, an agreement that has an uncertain future. Many of the funding provisions of the Compact expire in 2001 and, if not renewed, may have dramatic impacts on resource use. This in turn may lead to a much greater level of anthropogenic disturbance of what are now some of the world's most intact mangrove swamps.