Harvester Ants

Entrance to a colony of Harvester Ants, Pogonomyrmex spp.

Harvester Ants are large ants within the genera Pogonomyrmex or Ephebomyrmex with habitats west of the Mississippi with only one exception. There are 12 species found within Texas with the Red Harvester Ant, Pogonomyrmex barbatus being the most widespread. In addition to their large size, harvester ants can be identified by their conspicuous mounds in open areas. Grass around the nest is generally cleared, pebbles line the entrance, and foraging trails are often obvious.

Foraging trail of a harvester ant colony.

While harvester ants have a nasty sting, their primarily seed feeders, but will sometimes collect dead insects. They have characteristic large heads and powerful jaws used to carry food and crack seeds. The bounty gathered is stored in neat stacks within any number of sorting chambers up to 1.8 m (6 ft) underground. As with many ant species, harvester ants are social. There is a single queen who may live up to 15-20 years, but when she dies, she is not replaced. The fertile males and females leave the colony to reproduce while sterile females remain as workers with a lifespan of up to 1 year. During that year the young workers mainly fill roles keeping them inside the nest such as nest maintenance, while the older workers are more likely to fill roles taking them outside such as foraging and patrol. Their most well-known predator is the horned lizard whose diet is up to 65% harvester ant. Unfortunately, competition with imported fire ants and indiscriminate use of insecticides are reducing the number of harvester ants who already face the difficulty of a 1% success rate of new colonies.