Assessing the Viability of Scandinavian Brown Bear, Ursus arctos, Populations: The Effects of Uncertain Parameter Estimates

摘要: Based on data from radio-collared individuals, we present an analysis of the viability two small populations Scandinavian brown bear, Ursus arctos. The northern and southern had different demographic characteristics, even though population growth rate r variance s' were high in both (r= 0.13 sd= 0.180 north, r=0.15 s'=0.155 south). In environmental s5 was not significantly 0, whereas south = 0.003. south, this related to stochasticity survival youngest animals, which resulted increase with age population. contrast, probability showed a slight decrease age. Uncertainties obtained joint distribution bootstrap replications r, S5. Although uncertainty these estimates is quite large, it unlikely that relatively ( > 10 females ? 1 year old) will decline size less than I after 100 years. Analysis critical (i.e. where population's logarithmic zero) shows bear must be larger 3-4 or older secure positive rate. Similarly, if define viable as chance greater 90% during period years, 8 old north 6 south. This due reproductive rates. A mortality strongly reduce large populations.