Why do Red Harvester Ants Swarm?
Like other ant species, red harvester ants are divided into castes within their colonies. Worker ants are sterile females who forage for food and perform routine colony maintenance as their primary responsibilities. Male ants exist for the sole purpose of reproduction and die soon after mating. The fertilized females establish new colonies and become queens.
During red harvester ant mating swarms, winged males and females emerge from their colonies. They are attracted to each other by pheromones. After mating, the mated females shed their wings and establish new nesting sites.
Red harvester ant mating swarms occur annually in warm environments and at elevated heights. Red harvester ants are most active in warm temperatures, and mating swarms typically occur in the afternoon after rainfall or heavy storms. Although mating swarms occur between June and October, they are most common in the months of August and September. Red harvester ant mating swarms take place within a single day.
The swarming behavior of red harvester ants is commonly synchronized with nearby colonies. For this reason, it is common to witness large numbers of winged ants appearing in one area. Red harvester ants participate in "hill-topping," gathering around prominent points within a landscape — such as tall trees, chimneys and towers — while searching for mates.
While red harvester ants are known to dwell primarily outdoors, winged ants can accidently invade homes during swarming periods.