An introduction to hurricanes in the Caribbean

THIS ISSUE OF BIOTROPICA brings together, for the first time, a collection of case studies that document the damage to natural ecosystems and the initial recovery process from three recent hurricanes in the Caribbean. The majority of papers address the impact of Hurricane Hugo (1989) and subsequent recovery during the year following the hurricane at three sites: St. John in the U.S. Virgin Islands, Puerto Rico, and South Carolina on the U.S. mainland (Fig. 1). Hurricane Hugo triggered a rapid increase in the level of hurricane research, in part because it passed over two Long-Term Ecological Research sites (Luquillo Experimental Forest, Puerto Rico and North Inlet, South Carolina) which had ecological data that allowed comparisons of prehurricane and posthurricane conditions. Benefits of such long-term studies include the ability to separate damage caused by the recent hurricane from previous damage; to not depend on reconstruction of damage scenarios from historical evidence; and, to begin studies of recovery immediately. Hurricane Hugo also provided an opportunity to contrast hurricane damage in different environments: tropical and temperate, humid and dry, island and continental. In addition to studies of Hurricane Hugo, we include studies of the effects of Hurricane Gilbert (1988) on Jamaica and Mexico, and Hurricane Joan (1988) on Nicaragua (Fig. 1). We have emphasized studies of terrestrial ecosystems; hurricane impacts on marine and coastal ecosystems have been examined elsewhere (Woodley et al. 1981, BenitoEspinal & Benito-Espinal 1991, Finkl & Pilkey 1991). Hurricanes are frequent, large-scale disturbances in the Caribbean. During the period 18711964, zero to eleven hurricanes per year (average = 4.6, median = 8) occurred in the Caribbean (Alaka 1976), resulting in, for example, a return time of 21 yr for the island of Puerto Rico (Salivia 1972). The strongest Caribbean hurricanes typically originate off the western coast of Africa, gain strength as they pass westward over the Atlantic Ocean, and rapidly deteriorate when they reach the mainland somewhere between Panama and New England. Weaker hurricanes and tropical storms (wind speeds 63-119 km/hr) have their origins throughout the Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. With wind speeds of at least 119 km/hr and paths often tens of kilometers wide, hurricanes have a profound effect on plants, soils, animals, humans, and even landforms. Much attention is given to the destruction of property (Saffir 1991, Sparks 1991), and the loss of human lives in these storms. The effects of hurricanes on natural ecosystems (Fig. 2) have also been noted (e.g., Foster 1988) but are less understood. Studies in Puerto Rico suggest that hurricanes may have a major effect in structuring natural ecosystems in terms of age distribution of tropical forest trees (Doyle 1981, Weaver 1986, Lugo & Rivera-Batlle 1987), or biomass and species diversity (Crow 1980). These studies add to the accumulating evidence that suggests natural systems are largely organized by disturbance (Pickett & White 1985, Denslow 1987). The study of how natural ecosystems are altered by hurricanes and how they respond is essential to the understanding of how these systems are structured. Adding urgency to this study is the relationship between hurricanes and global climate change. Slight increases in surface water temperatures or periods of high rainfall in the I Received 28 July 1991, revision accepted 5 August 1991.