North American desert rodents in the family Heteromyidae live in an unpredictable environment characterized by extremes in temperature and food availability; therefore, the ability to hoard food is a vital adaptation. Although much laboratory research has investigated food-hoarding tactics of heteromyid rodents, data from natural systems are scarce. We used a combination of fluorescently labeled seeds and observations of focal individuals to evaluate food-hoarding behavior in wild Merriam's kangaroo rats (Dipodomys merriami) living in different competitive environments. There was considerable individual variation within populations in the tendency to larderhoard seeds in a burrow versus scatterhoard seeds in widely dispersed locations. [...]