Patterns of Food, Space and Diversity

Abstract

In a band of semi-arid grasslands and shrublands of the high basins of the American Southwest, one can find impressive numbers of nocturnal rodents. Species are both diverse and abundant in the traps of the rodent ecologist. One family in particular, the Heteromyidae, a family endemic to North America, has particularly rich associations: its members are usually far more abundant than those of all other families combined and it quite often displays three of its species on the same patch of ground (less than 1/5 hectare) at the same time. In fact, associations of four or even five species are not infrequently encountered and there is a report in the literature of six species taken in about 1/2 hectare (Hoffmeister & Goodpaster, 1954). Often, associations of Heteromyidae are joined by various cricetines including members of the genera Peromyscus, Onychomys, Reithrodontomys, Baiomys, Sigmodon and Neotoma.