PARENT SESSION
Contributed Oral Session 134: Forest Ecology: Reproduction and Recruitment
Thursday, August 11, 1:30 PM - 5:00 PM, Meeting Room 516 D, Level 5, Palais des congrès de Montréal
Acacia collinsii: seed dispersal by ants in a disturbed tropical dry forest in Costa Rica.
Zelikova, Tamara*,1, Sanchez, Leticia1, 1 University of Colorado-Boulder, Boulder, CO, USA
ABSTRACT- We investigated the effects of habitat type (forest versus open field) on seed dispersal of Acacia collinsii by ants in tropical dry forests of Costa Rica. We also assessed the quality of different ant species as seed dispersal vectors in habitats with different disturbance regimes. We compared the latency of response, dispersal distance, seed carrying time, dispersal destination, and the effects of habitat on dispersal services between several species of ants within the genus Pheidole and Ectatomma. Latency of response was shorter in the open field than in the forest. Both average dispersal distance and average seed carrying time were greater in the forest than in the open field. Seeds were more likely to remain untouched by ants in the open field than on the forest floor. Interspecific comparisons yielded that ants in the genus Pheidole were better seed dispersers because they recruited heavily to seeds, dispersed further, and were more efficient seed movers. Ectatomma riudum did not recruit workers to seed baits and carried seeds much shorter distances, frequently dropping seeds en route to their nests. Based on these observations, we conclude that life histories of disperser ants play an important role in determining the fate of seeds that fall to the forest floor.
Key words: myrmecochory, disturbance, ants, Acacia collinsii