PARENT SESSION
Oral Session #16: Disturbance in diverse systems: Flooding and other. Presiding: T. Stohlgren.
Monday, August 6, 2001. 1:00 PM to 5:00 PM. Hall of Ideas G.

Recovery from a triple disturbance: agriculture, hurricane and exotics in a Caribbean ant community.

Allen, Richard¹, Power, Alison¹, Flecker, Alexander¹, ¹

ABSTRACT- Caribbean forests are frequently disturbed by humans, through agricultural conversion, and naturally by hurricanes. Here we report on the effects of a hurricane on the ant community in a neo-tropical forest recovering from a legacy of agricultural conversion. From 1996 through 1998 we tracked the recovery of Caribbean forest from agricultural conversion on thirty-eight plots in Los Haitises National Park, Dominican Republic. Four abandoned agricultural habitats were sampled: pastures, mixed cropping habitats (conucos) abandoned recently, conucos abandoned for over ten years, and cacao groves. The ant community was sampled twice annually using ten pitfall traps for six days within each plot. In 1998 hurricane Georges heavily disturbed all of the plots. In 1999 and 2000 we resampled the ant community to assess changes brought about by the hurricane. The woody plant community, on all plots, was sampled once before and once after the hurricane. Ant diversity was generally higher in less disturbed habitats. Two exotic disturbance specialists (Wasmannia auropunctata and Solenopsis invicta) were found in nearly every plot sampled. Post-hurricane abundance was significantly higher on most plots regardless of prior agricultural type or changes in diversity or basal area of the plant community. W. auropunctata increased by 1,400% on some plots, accounting for most of the abundance increase. This third "disturbance," from the exotics in this system, may be dictating the tempo of recovery in this system.

KEY WORDS: ant diversity, exotic species, hurricane, community recovery