The presence of the parasitic flies Pseudacteon tricuspis (Diptera: Phoridae) influences the outcome of competitive interactions among red imported fire ants (Solenopsis invicta) and other ant species by reducing the foraging effort of S. invicta. These flies are diurnal while S. invicta are known to forage both diurnally and nocturnally. Nocturnal foraging by S. invicta potentially presents a temporal escape from the parasitism pressure of P. tricuspis. This study assessed the effects of P. tricuspis on foraging patterns of S. invicta colonies in the absence of resource competition. Ten treatment (flies present) and ten control (flies absent) colonies were maintained in separate greenhouse units under identical conditions. A food source of known mass was offered to both groups and removed and weighed after a 24hr period. Foraging observations were made daily and nightly while food was present. Diurnal foraging intensity was significantly less (P < 0.05) in treatment colonies relative to control colonies. However, the mean amount of food consumed over 24 hours was not significantly different (P=0.114). In fact, the average amount of food consumed was greater in the treatment group (0.205g) relative to controls (0.175g). Nocturnal foraging intensity was significantly greater (P < 0.05) in the treatment group. The results of this study appear to demonstrate a compensatory nocturnal foraging strategy among colonies that are challenged by this parasitoid.