However, due to uncertainty of the proportion of females breeding, we evaluated possible 2 reproductive scenarios. However, data were not available to estimate the effect of environmental variability on adult mortality rates or the proportion of females producing pups. We believe it is likely that environmental variation has a greater effect on pup survival than on adult survival or the proportion of females breeding. Due to the uncertainty of the effects of environmental variation on survival and reproductive rates, we evaluated 3 scenarios. We assumed that variation in survival was concordant with variation in reproduction, i.e., years of poor reproduction were associated with years of poor survival and years of good reproduction were associated with years of good survival.
Few data are available to estimate the frequency of catastrophic events in wolf populations.
The Wisconsin wolf population has experienced 2 epidemics during the past 17 years. To assess the effect of catastrophic events on the viability of wolf populations we evaluated 3 scenarios. The age distribution of starting populations were set to reflect stable age distributions based on the reproduction and survival rates. Whenever simulated populations exceed the biological carrying capacity, additional mortality was imposed to reduce the population back to carrying capacity. In all simulations, we assumed that the population was not harvested or augmented.