60 Mountain Lions of the Black Hills
because they are based on straight- line distances, which are not characteristic of how
mountain lions travel. This high rate of travel and the type of terrain traversed make
it difficult to keep up with dispersing lions. These issues also help to explain why people
who describe mountain lion sightings to wildlife professionals might not have their
observations verified; those lions could be 30 km away from the sighting location by
the time officials arrive at the site. Furthermore, lions are light- footed, and these
younger subadult lions that weight about 36 kg might not leave identifiable tracks at
the location of the sighting.
Home Ranges
When we began studying mountain lions, the territory size of male cats seemed
enormous, compared to the findings of other studies. For example, the average terri-
tory size for three males and three females was 797 km^2 (308 miles^2 ) and 159 km^2
(61 miles^2 ) (Fecske 2003). This average home range size for males and females repre-
sented about 9% and 2% of the entire Black Hills region and would imply that there
was enough area in the Black Hills to support about 11 territorial males and about
50 females. For males, at least, these large territories likely were a function of the low
population size, and during our activities to locate radio- collared males, we noted
movements across territorial borders. For example, Route 385 formed the border be-
tween the territories of two adult males; females were located on each side of the
highway. Males had been observed crossing the highway, and when captured they
seemed to be in excellent condition relative to battle scars, suggesting that home
ranges were so large that the probability that the two males encountered each other
was low, even when visiting and/or breeding with females within each other’s terri-
tory. Later home ranges, estimated when the population was approaching saturation
(i.e., the capacity of the Black Hills to support mountain lions), ranged in size from
251 to 2,314 km^2 for males and from 55 to 623 km^2 for females ( table 4.4; fig. 4.13).
The home range size differential was 3.7 to 4.6 times as large for males as for females;
this difference was a bit larger than that documented for mountain lions in north-
western Wyoming (1.4–1.9 [Lendrum et al. 2014]).
Table 4.3. Travel rates of male mountain lions that dispersed from the Black HillsMountain lion Days between locations Total distance traveled Travel rate
M16 267 1,067 km 4.0 km/day
M17 21 100.5 km 4.8 km/day
M19 7 75.6 km 10.8 km/day
M21 14 183.6 km 13.1 km/day
Average 7 7. 2 5 356.7 km 8.2 km/day
Source: D. J. Thompson.