Using hunter survey data to estimate wolf population
Sizes in montana, 2007-2009
Lindsey Rich, Montana Cooperative Wildlife Research Unit, University of Montana, Missoula,
Montana 59812
Betsy Glenn, Montana Cooperative Wildlife Research Unit, University of Montana, Missoula,
Montana 59812
Mike Mitchell ,* Montana Cooperative Wildlife Research Unit, University of Montana, Missoula,
Montana 59812
Justin Gude, Montana Fish, Wildlife, and Parks, Helena, Montana 59620
Carolyn Sime, Montana Fish, Wildlife, and Parks, Helena, Montana 59620
Reliable knowledge of the status and trend of carnivore populations is critical to their
conservation. In the Northern Rocky Mountains, wildlife managers need a time- and cost-
efficient method for monitoring the large, growing population of gray wolves (Canis lupus) at
a state-wide scale. We explored how hunter survey data could be incorporated into a multi-
year patch occupancy model framework to estimate the abundance and distribution of wolf
packs, wolves, and breeding pairs in Montana for 2007- 2009. We used hunter observations of
wolves to estimate the probability that a given landscape patch was occupied by a wolf pack,
and used additional data/models in combination with occupancy model output to provide
estimates of total number of wolves and number of breeding pairs. Our modeling framework
also allowed us to examine how geographic and ecological factors influenced occupancy
and detection of wolf packs. Our models provided estimates of number of packs, number of
wolves, and number of breeding pairs that were within 20 percent of Montana Fish, Wildlife,
and Parks minimum counts for 2007-2009. We found occupancy was positively related to
forest cover, rural roads, and elevation and detection probability was positively related to
hunter effort and forest cover. We believe that patch occupancy models based on hunter
surveys offer promise as a method for accurately monitoring elusive carnivores at state-wide
scales in a time- and cost-efficient manner.