Changes in Foraging Activity of the Southern Harvester Ant Pogonomyrmex badius (Latreille) in Response to Fire

The southern harvester ant Pogonomyrmex badius (Latreille) is common in the sandhill habitat of Florida, a habitat strongly influenced by fire. We documented changes in foraging activity of the ant in response to a planned burn in an area of sandhill. Measurements related to foraging activity were made several times before and after burning: number of foraging trunks and direction and length of each trunk, to estimate foraging area; number of individuals emerging from colony entrances; number of individuals outside colony entrances; number of individuals engaged in foraging; and number of items returned to colonies. Only number of individuals emerging from colony entrances and foraging area changed in response to the burn: both increased. We suggest that ecological conditions in the plots, namely the unfavorable ambient conditions often present and the low densities of colonies, in large part dictated the way in which foraging activity could change after the burn. The changes observed may be a general response of the southern harvester ant to changes in resource availability; however, other causes, such as alteration of physical structure in the vicinity of colonies, may underlie changes in foraging activity an these need to be examined