A major limitation on the study of collective behavior is the rate at which data can be gathered. We are collaborating with James Rehg and Tucker Balch at Georgia Tech to create an automated solution that will continuously track the positions of multiple interacting individuals and infer their behavior. These software tools will be widely applicable to studies of animal behavior, but development will focus on the challenging problems offered by ants, where multiple interacting animals must be simultaneously tracked. As a first step, we are using a prototype tracker to gather extensive data on the encounter rates of Temnothorax rugatulus scouts as they assess candidate nest sites. We will use this data to test a simple model for how encounter rate data can be used to assess population density, a key source of information for the coordination of social behavior in ants.