Revista Chilena de Historia Natural 75 (4): 751-756, 2002
RESEARCH ARTICLE
Population density and reproduction of two Peruvian leaf-eared mice (Phyllotis
spp.)
Population density and reproduction were studied in two leaf-eared mice (Phyllotis
spp.) in the Peruvian locality known as Lomas de Lachay. Density varied between 0-3 individuals haha<sup>-1</sup>
in P. andium, and between 0-12 individuals haha<sup>-1</sup> in P. amicus. An annual cycle of
population abundance was observed in both species. Phyllotis amicus showed no seasonal reproductive activity, but
P. andium had seasonal reproduction with pregnant females principally observed between July and September.
Differences in juvenile weight were related to litter size. It is likely that two young was the optimal litter size in the harsh and seasonal
xeric environment of Lomas de Lachay. Our results suggest that P. amicus maintains low, highly dispersed populations in
a harsh environment, and can reproduce at any time of the year, whereas P. andium appears to be a more irruptive
species closely tied to rainfall patterns.
Key words:
ecology,
Phyllotis, rodents, population, desert
