Chadwick P. Lehman, Erin E. Morrison, Brady Y. Neiles, Christopher T. Rota
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引用次数: 0
Abstract
Bobcats (Lynx rufus) are the most broadly distributed native felid in North America and have substantial ecological and economic importance. Despite this importance, little is known about factors influencing population dynamics of this cryptic carnivore. Given recent apparent declines in abundance, we investigated population growth rate (λ) for a bobcat population in the Black Hills, South Dakota, USA, 2016–2022. We constructed and evaluated a females-only matrix population model. Our estimate of asymptotic λ, derived from estimates of vital rates obtained over 6 years, was 0.85 (95% CI = 0.72, 1.02), which indicates that the vital rates in 2016–2022 were inadequate to sustain the population. Elasticity and sensitivity values were highest for changes in adult survival probability followed by, in order, changes in kitten and juvenile survival and adult reproductive contribution. Life-stage simulation analysis also supported that adult survival was most important; however, the juvenile survival (91 day–1 year) component of a bobcat's first year of life was also important and a stronger influence on population growth than the kitten survival (first 90 days) component. For the combination of survival and reproductive rates we estimated positive population growth required either annual adult survival >0.85 or 275-day juvenile survival >0.35, regardless of other vital rates. When assuming a baseline harvest rate of 23.5%, reducing the harvest rate to 9% led to a positive mean growth rate and a >0.50 probability of a growing population. Monitoring juvenile-to-adult harvest ratios can provide an indicator of age structure in the population, and we recommend restricting harvest when that ratio falls below 10%, particularly when managers lack research information on population growth.
期刊介绍:
The Journal of Wildlife Management publishes manuscripts containing information from original research that contributes to basic wildlife science. Suitable topics include investigations into the biology and ecology of wildlife and their habitats that has direct or indirect implications for wildlife management and conservation. This includes basic information on wildlife habitat use, reproduction, genetics, demographics, viability, predator-prey relationships, space-use, movements, behavior, and physiology; but within the context of contemporary management and conservation issues such that the knowledge may ultimately be useful to wildlife practitioners. Also considered are theoretical and conceptual aspects of wildlife science, including development of new approaches to quantitative analyses, modeling of wildlife populations and habitats, and other topics that are germane to advancing wildlife science. Limited reviews or meta analyses will be considered if they provide a meaningful new synthesis or perspective on an appropriate subject. Direct evaluation of management practices or policies should be sent to the Wildlife Society Bulletin, as should papers reporting new tools or techniques. However, papers that report new tools or techniques, or effects of management practices, within the context of a broader study investigating basic wildlife biology and ecology will be considered by The Journal of Wildlife Management. Book reviews of relevant topics in basic wildlife research and biology.