Habitat preferences of alpine marmots, Marmota marmota, were investiga
ted at two sites in the French Alps. The use of a logistic-linear mode
l allowed us to model the probability of marmot settlement in differen
t ecological situations. Marmots preferred sites with a southern or ea
stern aspect (where snow melts relatively early), intermediate slopes,
moderate plant cover, and a low level of human disturbance, and they
seemed to select their habitat according to a nested system. To test i
f habitat quality affected individual fitness, we investigated the eff
ects of sun exposure and two home-range characteristics on litter size
at emergence, frequency of female reproduction, and retention of subo
rdinates. Sun exposure and home-range size are two major components of
home-range quality that may affect individual fitness.