The effect of mammalian predator scent on the foraging behavior of Dipodomys merriami

Previous work has shown that kangaroo rats (Dipodomys) adjust foraging beha vior to perceived risks of predation assessed via visual and auditory cues. A field study was performed in the Mojave Desert to determine if D. merria mi also assesses predation risk via olfaction. The presence of mammalian pr edator urine was manipulated at food patches in two microhabitats (open and under shrubs) during two seasons and giving-up densities (GUDs) were measu red to quantify D. merriami's foraging behavior. In winter, D. merriami exh ibited a preference for feeding under shrubs but the presence of predator s cent in the shrub microhabitat significantly reduced foraging activity. In summer, D. merriami again exhibited a strong preference for the shrub micro habitat but no effect of predator scent was observed. These results indicat e that predator scent can affect kangaroo rat behavior suggesting that olfa ction is used by kangaroo rats to assess predation risk. The results thus p rovide a more complete description of how predators affect the foraging beh avior of desert rodents.