Year of Award


Document Type


Degree Type

Master of Arts (MA)

Degree Name


Department or School/College

Department of Economics

Committee Chair

Derek Kellenberg

Commitee Members

Carolyn Sime, Douglas Dalenberg, Mark Hebblewhite


calf weight gain, Montna, OLS, wolves


University of Montana


A novel sample of 18 western Montana cow-calf ranching operations were analyzed over a 16 year time period (1995-2010) using an ordinary least squares linear regression estimation model with robust standard errors focused on the potential effects wolves may have on average calf weight gain. Incorporating calf sex, calf breed, ranch, and year fixed effects into the estimation model, a vector of variables that changed both across ranches and over time were used to significantly explain (F = 59.32; p < 0.001) the variation in yearly average calf weaning weights on sample ranches with fairly good accuracy (R2 = 0.846). The use of hormone implanting (â=24.5), calf age (â=.34), annual aggregate precipitation (â=2.16), annual aggregate snowfall (â=-0.24), annual average temperature (â=4.27), and the standard deviation of NDVI (â=1.67) were found to be significant at least at the .1 level. One measure used to account for wolf presence on sample ranches based on yearly estimated wolf home range data from Montana Fish, Wildlife & Parks was found to have an insignificant effect on average calf weight (p = .569). The other measure used to account for wolf presence on sample ranches was found to be a significant factor on calf weight gain. On average, sample ranches that experienced at least one Wildlife Service (WS) confirmed wolf depredation on the ranch, weaned calves that were approximately 20 pounds lighter than ranches that did not have a WS confirmed wolf depredation in the same year, holding all else constant. The results suggest that calves on western Montana ranches that experience at least one WS wolf depredation in a year gain 20 pounds less weight than if there hadn’t been a WS confirmed wolf kill which directly correlates to decreased economic revenue received by affected ranchers.



© Copyright 2011 Joseph Ramler