Assessing extinction risks for westslope cutthroat trout in the upper Missouri River Basin using the BayVAM model. Their distribution continues to shrink, and several populations have become extinct within the last ten years. The USDA Forest Service and USDI Bureau of Land Management manage much of the remaining habitat for these trout. The BayVAM model is based on a stochastic life-history model that uses Bayesian priors for input parameters and produces a probabilistic prediction of future population levels. Regional biologists provided estimates of population parameters and of impacts of management activities on each population.
Results suggest that most populations are at extreme risk of extinction.
Livestock grazing and presence of non-native salmonids were two factors identified as having substantial effects. Modeling results led to a recommended strategy of broad-scale protection and targeted restoration based on the relative risks to populations. Pacific Northwest Research Station, Corvallis OR 97331, and Oregon State University, Corvallis, Oregon 97331. A predictive model has been developed to assess risk to anadromous salmonid populations associated with land management activities. These large-scale, slowly changing processes provide a constraint on the set of possible wood patterns in the channel.