Mountain Lions of the Black Hills

52 Mountain Lions of the Black Hills

similar results (Clark et al. 2014). Also, the number of vehicle kills and removals in-
creased, along with deaths from other causes (fig. 4.5), and 89% of resident males
showed moderate to severe scarring from interactions with other males (fig 4.6) during
this period of population increase and saturation (Thompson 2009). This last finding
was much diff er ent from what we observed in our first captures, where adult males in
the range of 3.5 to 6.5 years had virtually no injuries that would have been caused by
interactions with other territorial males. When we combined all of our empirical infor-
mation, we were confident that our estimates were reasonable for the species.
From about 1999 to 2005, we also captured 15 kittens from five unique litters
(fig. 4.7), which averaged 3 kittens/litter initially, with a 5:1 male to female sex ratio
(Thompson 2009). One kitten died from unknown causes, and one litter (n = 4) died
owing to infanticide. The remaining litters and marked animals reached in de pen dence,
resulting in a survival rate of 0.67, which was similar to what other studies had docu-
mented (Lindzey et al. 1988) but lower than for kittens in the Greater Yellowstone
Northern Range (0.90 [Ruth et al. 2011]) and in west- central Montana (0.78 [Robin-
son et al. 2014]). Later estimates of kitten survival for work conducted after the start
of the mountain lion harvest were based on the capture of 25 litters (Jansen 2011).
Overall litter size was 3.0 kittens per litter, and the sex ratio was 5.33:1 (16 males,
3 females). Kitten survival averaged 0.62 ± 0.117 (Jansen 2011).

35

30

25

20

15

Total mor

tality (%)

10

5

0

VehicleRemova

l

Snar

e

Unknow

n

Interac

tion Illegal Legal

EmaciationAccidentalDr

owning

Fire

figure 4.5. Mountain lions are vulnerable to many causes of mortality. Mortality events
(n = 85) were documented for cougars in the Black Hills, 1998–2005. “Removal” refers to
lions that were euthanized by the South Dakota Department of Game, Fish and Parks for
safety (animals within towns and cities or those that caused deaths of domestic livestock
or pets). “Accidental” mortalities were due to our capture activities. Thompson 2009.