Intraspecific competition is important in determining habitat utilization by members of a single species. Effective use of habitat may involve partitioning the available resources: space, time and food among individuals of different age, sex, and/or reproductive state. Numerous publications deal with interspecific competition (McCloskey and Fieldwick 1975, Cody 1973, Rosenzweig 1973, Stewart and Levin 1973, Gaby 1972, Brown 1971, Koshkina 1971, Sheppe 1967, Caldwell and Gentry 1965, Cameron 1964, Clough 1964, Gause 1932), but little has been written on intraspecific competition among populations of organisms in nature.