Cost-Benefit Analysis of Mountain Lion Management for the Recovery of Endangered Sierra Nevada Bighorn Sheep

Abstract

We evaluated the consequences of different predator management strategies and the subsequent effects on time and cost to recovery for federally endangered Sierra Nevada bighorn sheep. Based on data collected during 1995-2009, we used stage based demographic modeling to estimate vital rates in three isolated herds, accounting for sampling error and variance. Using those vital rates we predicted the time and associated cost for the population to meet delisting goals. We found recovery time increased from 17.3 to 28.6 years using a density independent model and from 25.9 to 38.6 years using a density dependent model for different mountain lion management strategies. Commensurate cost increases of over 10 million dollars (unadjusted cost) result in either case. Our study suggests that appropriate levels of predator management will result in shorter recovery times and reduced cost of recovery through ensuring the availability of translocation stock. To be most effective, mountain lion management strategies should be population-specific because of underlying differences in predation rates for different herds.