Proceedings of the Ninth Mountain Lion Workshop - Carnivore ...

% Puma Use
45
40
35
30
25
20
15
10
5
0
Day
Night
0 - 5 5+ - 10 10+ - 20 20+ - 40 40+ - 100 100+
Acre s
Figure 3. Percent use by property parcel size class, day vs. night, for GPS collared pumas
in rural developed zone of California’s Western Sierra Nevada, 2002-2006.
Discussion
We found evidence that low-density rural development, with associated highways and
dense housing developments, resulted in fragmented puma habitat. Our results were
consistent with attributes of a source-sink population structure, disrupted connectivity of
landscapes for pumas, and the creation of habitat patches that pumas avoided in their
developed-zone home range areas.
Survival and dispersal parameters were obtained from a small sample, but were
consistent with a source-sink population and differed from our expectations for a habitatlimited,
or an unfragmented population structure. The 12-month mortality rate for all
pumas in our sample, 31%, was greater than annual mortality rates from unhunted
populations in other western states of 12% to 28% (Lindzey et al. 1988, Anderson et al.
1992, Beier and Barrett 1993, Logan and Sweanor 2001). Mortality for the Western
Sierra pumas was comparable to the higher mortality figures from hunted puma
populations, reported as 27%, 0% to 27%, and 32% (Ashman et al. 1983, Robinette et al.
1997). Our subadult puma 12-month mortality rate, 40%, was also considerably greater
than the 24% annual mortality rate reported from an expanding population in New
Mexico (Sweanor et al. 2000), and the 26% rate from a habitat-limited population in
Florida (Maehr et al. 2002).
However, 12-month mortality in the undeveloped zone, 16.7%, was among the lowest
reported in the literature, while the 42.9% mortality rate in the developed zone exceeded
Proceedings of the Ninth Mountain Lion Workshop
140