Size and composition of white-tailed deer groups in a tropical dry forest in Mexico

The tropical dry forest of ''Chamela'' in the state of Jalisco, Mexico, is distinguished by highly seasonal food and water availability, year-round dense cover understory, and constant presence of predators species of the white-tailed deer. Therefore, frequent small groups and solitary individuals should be expected. To test this hypothesis, the size and composition of white-tailed deer groups was estimated between July 1989 and June 1993. A total of 508 deer was counted in diurnal walks along 756 km. The mean size of the groups was 1.5 individuals (range = 1.0 to 1.9), with a mode of one for the whole study period. Solitary individuals were frequent throughout the year. Females with young comprised the most frequent social group. No groups of males were found. Group size was related with the life cycle, habitat and predation, and was smaller than has been found in other studies.