influence du climat et de la prédation sur l'utilisation de l'habitat et la ...

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5.4. Results
Habitat selection
At the microhabitat scale, selecti on fo r dens was obvious because juveniles were using
dens in 47% of observati ons while we never fo und dens in the random locati ons we sampled
(Fig. 5.1 a) . Juveniles also selected sites characteri zed by a hi gh protecti ve cover, low air
temperature, and low wind speed (Fig. 5. l a, Table 5.1). The hazard rati os allowed us to
quantify this selecti on and indicate that a 10% increase in protecti ve cover was associated
with a 69% increase in selection, that a 1°C increase in temperature was associated with a
2 1 % decrease in selecti on and that a 0.1 mis increase in wind speed was associated with a
20% decrease in selection (Table 5.1). Wh en using a tree, juveniles selected large trees but
did not signi ficantly use any tree species compared to aspens (Fig. 5. J b, Table 5. J).
According to the hazard rati o, a 10 cm increase in the circumfe rence of the tree was
associated with a 72% increase in selecti on (Table 5.1).
At the local scale, juveniles selected areas with low herb cover and wi th cedar trees as
dominant tree species (Fig. 5.2, Table 5.1). The hazard ratios indicate that a 10% increase in
herb cover was associated with a 14% decrease in selecti on and that the presence of cedar as
dominant tree species was associated with a J 36% increase in selection compared to when
aspen was dominant (Table 5.1).