Conservation of at-risk species is aided by reliable forecasts of the consequences of environmental change and management actions on population viability. Forecasts from conventional population viability analysis (PVA) are made using a two-step procedure in which parameters are estimated, or elicited from expert opinion, and then plugged into a stochastic population model without accounting for parameter uncertainty. Recently developed statistical PVAs differ because forecasts are made conditional on models fitted to empirical data. The statistical forecasting approach allows for uncertainty about parameters, but it has rarely been applied in metapopulation contexts where spatially explicit inference is needed about colonization and extinction dynamics and other forms of stochasticity that influence metapopulation viability. We conducted a statistical metapopulation viability analysis (MPVA) using 11 yr of data on the federally threatened Chiricahua leopard frog (Lithobates chiricahuensis) to forecast responses to landscape heterogeneity, drought, environmental stochasticity, and management. We evaluated several future environmental scenarios and pond restoration options designed to reduce extinction risk. Forecasts over a 50-yr time horizon indicated that metapopulation extinction risk was <4% for all scenarios, but uncertainty was high. Without pond restoration, extinction risk is forecasted to be 3.9% (95% CI 0-37%) by year 2066. Restoring six ponds by increasing their hydroperiod reduced extinction risk to <1% and greatly reduced uncertainty (95% CI 0-2%). Our results suggest that managers can mitigate the impacts of drought and environmental stochasticity on metapopulation viability by maintaining ponds that hold water throughout the year and keeping them free of invasive predators. Our study illustrates the utility of the spatially explicit statistical forecasting approach to MPVA in conservation planning efforts.

中文翻译：

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一种统计预测方法，对种群的生存力进行分析。

通过对环境变化的后果以及管理措施对种群生存力的可靠预测，可以帮助保护处于危险中的物种。传统的种群生存力分析（PVA）的预测使用两步过程进行，在该过程中，对参数进行估计或从专家的意见中得出参数，然后将其插入随机人口模型中，而无需考虑参数不确定性。最近开发的统计PVA有所不同，因为预测是根据适合于经验数据的模型进行的。统计预测方法考虑到参数的不确定性，但很少用于需要在空间上明确推断定植和灭绝动力学以及影响随机种群生存力的其他形式随机性的随机种群环境中。我们使用11年联邦受威胁的奇里卡瓦豹蛙（Lithobates chiricahuensis）的数据进行了统计种群生存力分析（MPVA），以预测对景观异质性，干旱，环境随机性和管理的响应。我们评估了几种未来的环境情景和旨在减少灭绝风险的池塘恢复方案。在50年的时间范围内的预测表明，在所有情况下，种群灭绝的风险均低于4％，但不确定性很高。如果不进行池塘恢复，到2066年，灭绝风险预计将为3.9％（95％CI 0-37％）。通过增加水文期来恢复六个池塘，可将灭绝风险降至<1％，并大大降低不确定性（95％CI 0-2） ％）。我们的结果表明，管理者可以通过维持全年蓄水的池塘并使它们免受侵入性掠食者的侵害来减轻干旱和环境随机性对种群生存力的影响。我们的研究说明了空间明确的统计预测方法在保护规划工作中对MPVA的实用性。