School of Biological Sciences, Louisiana Tech University, Ruston, LA 71272, U.S.A.
CSIRO Land and Water, Dutton Park, QLD 4102, Australia.
Conserv Biol. 2018 Feb;32(1):35-49. doi: 10.1111/cobi.12963. Epub 2017 Oct 30.
In 2014, the Fish and Wildlife Service (FWS) and National Marine Fisheries Service announced a new policy interpretation for the U.S. Endangered Species Act (ESA). According to the act, a species must be listed as threatened or endangered if it is determined to be threatened or endangered in a significant portion of its range (SPR). The 2014 policy seeks to provide consistency by establishing that a portion of the range should be considered significant if the associated individuals' "removal would cause the entire species to become endangered or threatened." We reviewed 20 quantitative techniques used to assess whether a portion of a species' range is significant according to the new guidance. Our assessments are based on the 3R criteria-redundancy (i.e., buffering from catastrophe), resiliency (i.e., ability to withstand stochasticity), and representation (i.e., ability to evolve)-that the FWS uses to determine if a species merits listing. We identified data needs for each quantitative technique and considered which methods could be implemented given the data limitations typical of rare species. We also identified proxies for the 3Rs that may be used with limited data. To assess potential data availability, we evaluated 7 example species by accessing data in their species status assessments, which document all the information used during a listing decision. In all species, an SPR could be evaluated with at least one metric for each of the 3Rs robustly or with substantial assumptions. Resiliency assessments appeared most constrained by limited data, and many species lacked information on connectivity between subpopulations, genetic variation, and spatial variability in vital rates. These data gaps will likely make SPR assessments for species with complex life histories or that cross national boundaries difficult. Although we reviewed techniques for the ESA, other countries require identification of significant areas and could benefit from this research.
2014 年，美国鱼类和野生动物管理局（FWS）和国家海洋渔业局宣布了一项美国濒危物种法案（ESA）的新政策解释。根据该法案，如果一个物种在其分布范围内的重要部分被确定受到威胁或濒危，那么该物种必须被列为受威胁或濒危物种（SPR）。2014 年的政策旨在通过确立如果相关个体的“移除将导致整个物种濒危或受到威胁”，那么一部分范围应被视为重要的，从而提供一致性。我们审查了 20 种用于评估物种分布范围内的一部分是否根据新指南具有重要性的定量技术。我们的评估基于 FWS 用于确定物种是否值得列入清单的 3R 标准-冗余（即，免受灾难的缓冲）、弹性（即，承受随机性的能力）和代表性（即，进化的能力）。我们确定了每种定量技术的数据需求，并考虑了在典型稀有物种数据限制的情况下可以实施哪些方法。我们还确定了可以在有限数据下使用的 3R 代理。为了评估潜在的数据可用性，我们通过访问物种状况评估中的数据来评估 7 个示例物种，这些数据记录了在列出清单的决策过程中使用的所有信息。在所有物种中，都可以使用至少一种针对每个 3R 的指标来评估 SPR，或者在有大量假设的情况下进行评估。弹性评估似乎受到数据限制的限制最大，许多物种缺乏关于亚种群之间的连通性、遗传变异和关键比率空间变异性的信息。这些数据差距可能会使具有复杂生活史或跨越国界的物种的 SPR 评估变得困难。尽管我们审查了 ESA 的技术，但其他国家也需要确定重要区域，并且可以从这项研究中受益。
