D3094: Host preference of searching parasitic thatch ant queens

Socially parasitic ant queens reproduce by finding suitable host nests with which to establish. They need to time their reproduction to take advantage of host phenology, and navigate a complex environment using olfactory and visual cues. There are also facultatively socially parasitic ants that can reproduce with secondary polygyny using conspecific host nests. The temperate North American species Formica obscuripes is said to be facultatively socially parasitic. Queens of F. obscuripes that are looking to join a nest where both conspecific and heterospecific host colonies are abundant therefore have a choice between the two. We describe the phenology of Formica obscuripes queens, and test them in Y-tube choice experiments using olfactory and visual cues from colonies of Formica obscuripes and their host Formica podzolica. We expect that in the choice experiments, F. obscuripes queens would prefer the smaller F. podzolica that would be less able to resist incursions.