Population ecology of Proechimys guairae (Rodentia: Echimyidae)

Abstract

An ecological study of Proechimys guairae in Venezuela was made based on marking and recapturing of individuals at 225 trapping stations distributed over 9 ha. The trappability of individuals was >50% in most sampling events; there was no difference in capture rate between marked or unmarked individuals, or males and females. Adult individuals were present throughout the sampling period, but juveniles appeared at the beginning of the rainy season and disappeared in the dry season. Pregnant or lactating females were observed during most sampling periods. Most reproductive activity was concentrated from the middle of the dry season through the wet period. Estimated density was 1-3.5 individuals/ha; that variation appeared to be related to weather fluctuation and resource availability. Estimated effective population size (Ne) was 3-20 individuals/ha. Estimated home ranges value were significantly different for females and males. Adult females had no overlap of their home range, suggesting female territoriality. Home range of males did overlap. Data were compared with those of other species. Some ecological conditions that might have favored speciation guided by chromosomal mutations characterize P. guairae.