Short-Term Effects of Hurricane Gilbert on Terrestrial Bird Populations on Jamaica

Four months after Hurricane Gilbert we resampled 10 habitats that were sampled previously in December 1987. Overall, we found no change in the total number of species nor in the mean number of individual birds detected. The mean number of individuals declined in three montane habitats (cloud forest, pine plantation, and coffee plantation), where structural damage to tree trunks and branches was often severe, and trees were still defoliated. In the mountains, higher proportions of nectarivores and fruit/seedeaters declined than insectivores. We found increased mean numbers of individuals in two lowland sites (wet limestone forest and mangroves), where structural damage to trees was also severe, but where new foliage was present. Mean numbers of individuals did not change in five other lowland habitats, despite varying levels of vegetation damage. Populations of several species declined in some habitats and increased in others, a pattern consistent with interhabitat migration. Population declines in montane habitats were related to diet, suggesting that Hurricane Gilbert's greatest stress on Jamaica's montane bird populations occurred after its passage rather than during its impact. Frequent hurricanes may contribute to some of the commonly observed characteristics of the Caribbean avifauna.