CHAPTER 4: KNVIRONMENT.Vl. CONSK0UENt:i':.S 



Montana geography that presents intermingled valleys and mountainous terrain, and a patchwork of 

 human settlement, variable wild prey densities, and livestock distribution. Future wolf population growth 

 in Montana will probably be determined by social conflicts between wolves and humans. At present, 

 there is no reliable method to determine "social tolerance." How fast the population grows and where 

 wolves will be found will differ across the five alternatives that reflect a spectrum of social tolerance and 

 management approaches. Therefore, the total number of wolves was predicted differently for each 

 alternative. Once the total number was predicted, the number of breeding pairs is also predicted using the 

 mathematical relationships that describe the correlation between the minimum number of wolves in the 

 fall population and the number of breeding pairs for the gray wolf population in the State of Montana, 

 based on historical data (USFWS unpubl. data). 



For Alternative 1 (No Action), the gray wolf stays listed and managed according to the original recovery 

 plan and the Yellowstone EIS (USFWS 1994a). The number of wolves in the experimental population 

 area was predicted by assuming the population would grow at 22% per year - the same growth rate 

 assumed for the Yellowstone EIS. The number of wolves in the Northwestern Montana Recovery Area in 

 2015 was predicted using population performance between 1986 and 2001 . The number of wolves in 

 each area was added together to predict the total number of wolves in the Montana population. 



For Alternatives 2 (Updated Council) and 3 (Additional WolO. wolf numbers were estimated by 

 analyzing historical data for the Montana portion of the tri-state population from 1986-2001 (USFWS 

 unpubl.) Historical finite rates of growth (lambda) were assumed to be representative of future population 

 performance and applied to the predicted Montana wolf population at the time of delisting in 2003. 

 Implementation of liberal management tools was assumed to decrease the population growth rate by 50%. 

 The decreased growth rate was applied to the population from the year liberal tools are implemented until 

 2015. 



Owing to the uncertainty about how fast the wolf population will actually increase. FWP estimated the 

 size of a future wolf population according to a low growth rate and a high growth rate. The low growth 

 rate is derived from actual historical data. The high growth rate was assumed to be double the low growth 

 rate. FWP expects the number to actually be near the low end of the range. The Montana wolf 

 population may stabilize at numbers at or near the adaptive management trigger so that liberal tools may 

 not be available every year between 2003 and 2015. The population could still increase or decrease from 

 year to year. 



For Alternative 4 (Minimum WolO, wolf numbers are capped near the recovery goals. Aggressive 

 management and control is assumed to limit the population at or near the cap. 



For Alternative 5 (Contingency), wolf numbers were predicted using the same method as Alternatives 2 

 and 3. However, FWP could only implement some of the liberal management tools because of certain 

 restrictions imposed by federal regulations. Therefore, the population growth rate was reduced by only 

 25% (rather than 50%) between the time that liberal management tools are implemented and 2015. The 

 wolf population may stabilize at numbers at or near the adaptive management trigger so that liberal tools 

 may not be available every year between 2003 and 2015. The population could still increase or decrease 

 from year to year. 



Prey Populations and Hunter Opportunity 



The gray wolf is an effective predator of ungulates. The impact on ungulate population dynamics can 

 usually be gauged in relation to other environmental factors, such as weather, and what other species are 

 present in the sy.stem. For example, wolf predation may accelerate declines in ungulate populations 

 already negatively affected by severe winters and even slow the rale of population recovery afterwards - 



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