RESPONSES OF TREE SPECIES TO HURRICANE WINDS IN SUBTROPICAL WET FOREST IN PUERTO-RICO - IMPLICATIONS FOR TROPICAL TREE LIFE-HISTORIES

1 The effect of a category 4 hurricane (Hurricane Hugo, 18 September 1 989) on subtropical wet forest in Puerto Rico was examined at stand an d species levels with respect to the frequency of tree damage, mortali ty, and resprouting. Data were collected from a 16-ha plot of secondar y forest consisting of approximately 13 000 trees >10 cm DBH represent ing 88 species. 2 Roughly one-quarter of the trees suffered some type of damage involving the main stem, and mortality due to the hurricane was 9%. Mortality among trees was primarily due to uprooting and broke n stems. Many surviving trees sprouted new branches following the hurr icane, indicating that this was an important component of stand recove ry following hurricane damage. 3 Patterns of species-specific damage a nd recovery (investigated using 26 common species) appeared to form tw o distinct groups. One group ('pioneers'), represented by three specie s, suffered a high frequency of stem breakage and mortality during the hurricane and had a low capacity to sprout new branches after being d amaged. The remaining species ('nonpioneers') lost many branches durin g the hurricane, thereby suffering low to moderate stem damage and mor tality, and sprouted many new branches following the hurricane. Stem b reakage and related species-specific characteristics were significantl y correlated with wood density and shade tolerance. 4 Species exhibite d few significant size-specific relationships (using DBH) with respect to hurricane damage, mortality, or resprouting, with the exception of branch damage, which often increased as a function of tree size. 5 Th e study revealed significant differences among tree species in the deg ree and type of damage suffered during a hurricane and in the ability to recover from damage and resume a position in the forest canopy. Non pioneers dominate early in recovery because of the ability to survive a storm and sprout new branches following the storm, while the immedia te impact of a hurricane on the abundance of pioneer species is strong ly negative.