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Pogonomyrmex californicus, invasive species, climate change, food preference, foraging, Bernard Field Station


Climate change can greatly affect the foraging behavior of ants. We investigated whether Pogonomyrmex californicus, Harvester ants, change their foraging behavior and their food preference depending on the time of day. We hypothesized that the Harvester ants would likely forage for food toward the evening. We also hypothesized that the Harvester ants would be less selective while foraging for food during the day because ants would need to expend more energy to forage during higher temperatures. To analyze the foraging habits three food sources—seeds, insects, and cotton balls soaked in sucrose—were provided to five ant colonies. Observations were taken during the day at and at night. We did not find evidence in support of our hypotheses. It was also found that ants preferred to eat during the day. Although we did not expect the ants to show a foraging preference during the daytime, the ants showed a preference for seeds over the insects and sugar solution during the day.