Males burn themselves out quickly from the exertion of fighting in the aerial swarm. Females spend the rest of their adult lives feeding on nectar and pollen and basking on the sand in the cool mornings and late afternoons. Apparently they are developing the large eggs that each hatch into a large, vigorous planidium larvae, which then burrows actively in the sand until it finds a host. Lek sites are on average 120 m apart, and the landing diameter of each lek site is an average of 15 m. Most lek sites have not moved positions in the nearly 20 years that we have been censusing them, with one interesting exception of a lek located on top of a dune ridge.
Most lek sites are on mid-dune slopes or swales.
While no new lek sites have appeared in this study area, we do see lone males engaging in aerial swarm behavior here or there in odd places, suggesting that there is always a potential for a new lek site to form. Nonetheless, the persistence of these traditional sites is impressive. We investigated the leading alternative hypotheses, which consist of males being attracted to some kind of environmental swarm marker convention, but the data show no evidence of any such environmental marker. Leks sites are randomly distributed in suitable habitat. In fact, our efforts to find such an environmental marker by measuring all conceivable environmental variables that might attract flies resulted in a large study of the vegetation and physical geography of the sand-dune ecosystem itself.