Mountain Lions of the Black Hills

114 Mountain Lions of the Black Hills

tissue collection, and those estimates could be used to adjust the availability of DNA-
marked lions in our analyses. We adjusted our estimates assuming that natu ral
mortality occurred prior to harvest, during half of the harvest season, and throughout
the harvest season, to provide an indication of the size of the effect (Juarez et al. 2016;
t a b l e 7. 5). These adjustments reduced the availability of DNA- marked lions from 32
to 31 in 2012 and from 28 to 26 in 2013 ( t a b l e 7. 5).
Estimates of the availability of marked lions (both radio- collared and DNA- marked)
were then used to estimate population size ( t a b l e 7. 6). The estimates obtained from
radio- collared mountain lions were 177 and 188 for 2012 and 2013, respectively, and
were not significantly diff er ent from each other, although the pattern suggested the
potential for a slight population increase. Alternatively, the estimates from DNA-
marked lions averaged 259 and 157 for 2012 and 2013, respectively. These estimates
of population size derived from DNA- marked mountain lions, similar to those based
on radio- collared lions, were not significantly diff er ent from one another; however,
they indicated that the population could have declined by about 100 individuals
( t a b l e 7. 6). This pattern of potential population decline, although again not statisti-
cally significant, was in line with our estimates of the number of breeders (NB;
t a b l e 7. 5), which supported population decline, and it also provided support for the
population model we used to estimate population size. In sum, the use of ge ne tics to
estimate population size seemed promising, even though we had many assumptions
that would need to be addressed or eliminated (such as focusing significant effort on
biopsy- darting mountain lions within a short period just prior to harvest, to maximize

Table 7.5. Radio and DNA- marked mountain lions (≥2 years of age) availability

and harvest for 2012 and 2013

2012 2013

Radio

DNA

Radio

DNA

NMPH NMHH NMTH NMPH NMHH NMTH

Mountain
lions
available

33 32 32 31 40 28 27 26

Marked
mountain
lions
harvested

11 7 7 7 9 8 8 8

Total
harvested

63 63 63 63 50 50 50 50

Source: Juarez 2014.
Note: Three DNA- marked availability estimates were derived: natu ral mortality occurred only prior to the
harvest season (NMPH), a midpoint in which natu ral mortality occurred during half of the harvest season
(NMHH), and natu ral mortality occurred throughout the harvest season (NMTH).