Summed Range-size Rarity of Imperiled Species in the United States

This map displays the summed range-size rarity of species in the lower 48 United States that are protected by the Endangered Species Act and/or considered to be in danger of extinction. It is part of the Map of Biodiversity Importance (MoBI) data collection, a series of maps that identify areas of high importance for protecting species from extinction in the contiguous United States. Building on habitat suitability models for 2,493 of the nation’s most imperiled species, and information on range size and degree of protection derived from those models, the MoBI project provides a series of maps that can help inform conservation efforts. This map depicts summed range-size rarity for Critically Imperiled (categorized by NatureServe as “G1”), Imperiled (“G2”), and ESA-listed (i.e., species listed as Endangered or Threatened under the Endangered Species Act) species in the following groups: Vertebrates (birds, mammals, amphibians, reptiles, freshwater fishes; 326 species) Freshwater invertebrates (mussels and crayfishes; 233 species) Pollinators (bumblebees, solitary bees, butterflies, and skippers; 63 species) Vascular plants (1,871 species) High values identify where species with very small ranges (and thus fewer places where they can be conserved) are likely to occur; the presence of multiple imperiled species contributes to higher scores. Habitat models for most species were generated using the random forest algorithm. Data to train the models came from the NatureServe Network (e.g. state Natural Heritage Programs) supplemented by data from Global Biodiversity Information Facility, and other publicly available sources of population and locality data. Environmental predictors used for the modeling include representations of terrain, climate, land cover, soils, and hydrology. The modeling resolution for terrestrial species was either 30-m (most species) or 330-m (some wide-ranging species). Models for aquatic species used the medium resolution National Hydrography Dataset (NHD) as the modeling unit. For species not amenable to random forest modeling, habitat maps were derived by buffering locality data and/or building simple deductive models based on habitat information. NatureServe converted habitat maps to a 330-m raster to provide a consistent unit of aggregation and avoid revealing the precise location of sensitive species. Range-size rarity for each species in the inverse of the total area mapped as habitat (using the 330-m raster). Summed range-size rarity is the sum of the range-size rarity values for all species with habitat that overlaps a cell. These data layers are intended to identify areas of high potential value for on-the-ground biodiversity protection efforts. As a synthesis of predictive models, they cannot guarantee either the presence or absence of imperiled species at a given location. For site-specific decision-making, these data should be used in conjunction with field surveys and/or documented occurrence data, such as is available from the NatureServe Network. For more information, see: Hamilton, H., Smyth, R.L., Young, B.E., Howard, T.G., Tracey, C., Breyer, S., Cameron, D.R., Chazal, A., Conley, A.K., Frye, C. and Schloss, C. (2022), Increasing taxonomic diversity and spatial resolution clarifies opportunities for protecting imperiled species in the U.S.. Ecological Applications. Accepted Author Manuscript e2534. https://doi.org/10.1002/eap.2534 Note that the above citation is based on the MoBI 2020 product and does not reflect the most current information. Please contact NatureServe for more information. This data supersedes the MoBI 2020 data which can be found here. A summary of changes between MoBI 2020 and 2024: Species included: MoBI 2024 includes 2,493 species, compared to 2,216 in MoBI 2024. Due to a combination of taxonomic updates and global rank/ESA status changes, 177 species from the 2020 product were removed while 454 species were added to this 2020 product. All taxonomic groups included in MoBI 2020 are included in the 2024 product, with the addition of several solitary bee genera. Scale changes: We increased the resolution from 990-m to 330-m for all MoBI products. Due to this resolution increase, we recommend caution conducting direct comparisons between the MoBI 2020 and MoBI 2024 products. To download data as a layer package, navigate here.本地图展示了美国本土48州内，受《濒危物种法》（Endangered Species Act）保护，或被认定为濒临灭绝风险的物种的范围大小稀有度总和（summed range-size rarity）。它属于“生物多样性重要性地图集（Map of Biodiversity Importance, MoBI）”数据集合的一部分——该系列地图用于识别美国本土范围内对物种灭绝保护具有高优先级的区域。该项目基于全美2493种最受威胁物种的栖息地适宜性模型，以及从这些模型中提取的物种分布范围与保护程度信息，生成了一系列可辅助保护决策的地图。本地图描绘了以下类群中，极危（NatureServe分类为“G1”）、濒危（“G2”）以及列入《濒危物种法》（即被列为濒危或受威胁物种）的物种的范围大小稀有度总和： - 脊椎动物（vertebrates，鸟类、哺乳类、两栖类、爬行类、淡水鱼类；共326种） - 淡水无脊椎动物（freshwater invertebrates，蚌类与螯虾；共233种） - 传粉者（pollinators，熊蜂、独居蜂、蝴蝶与弄蝶；共63种） - 维管植物（vascular plants，共1871种） 高数值区域代表分布范围极小（因此可用于保护的栖息地更少）的物种大概率出现的区域；同时存在多种受威胁物种会推高该栅格单元的评分。多数物种的栖息地模型采用随机森林（random forest）算法构建。用于训练模型的数据来自自然保护协会（NatureServe）网络（例如各州自然遗产项目），并补充了全球生物多样性信息设施（Global Biodiversity Information Facility）以及其他公开可获取的种群与分布点数据。建模使用的环境预测变量包括地形、气候、土地覆盖、土壤与水文相关表征数据。陆地物种的建模分辨率为30米（多数物种）或330米（部分广布物种）。水生物种的模型以中等分辨率的国家水文数据集（National Hydrography Dataset, NHD）作为建模单元。对于不适用于随机森林建模的物种，其栖息地地图通过对分布点数据进行缓冲区分析，或基于栖息地信息构建简单演绎模型得到。自然保护协会（NatureServe）将所有栖息地地图统一转换为330米栅格（raster），以保证聚合单元的一致性，同时避免泄露敏感物种的精确分布位置。每个物种的范围大小稀有度为其被映射为栖息地的总面积的倒数（采用330米栅格计算）。范围大小稀有度总和指的是所有栖息地与某一栅格单元重叠的物种的范围大小稀有度数值之和。这些数据图层旨在识别具有高潜在实地生物多样性保护价值的区域。作为预测模型的合成结果，它们无法保证某一特定位置存在或不存在受威胁物种。针对特定地点的决策制定时，应将这些数据与野外调查及/或已记录的物种出现数据（例如可从自然保护协会（NatureServe）网络获取的数据）结合使用。如需更多信息，请参阅：Hamilton, H., Smyth, R.L., Young, B.E., Howard, T.G., Tracey, C., Breyer, S., Cameron, D.R., Chazal, A., Conley, A.K., Frye, C. 及 Schloss, C. (2022)，《增加分类学多样性与空间分辨率可明确美国受威胁物种的保护机遇》，《生态应用》（Ecological Applications），已接收作者手稿e2534。https://doi.org/10.1002/eap.2534 请注意，上述引用基于MoBI 2020版本数据，并未反映最新信息。如需更多信息，请联系自然保护协会（NatureServe）。本数据取代了可在此处获取的MoBI 2020版本数据。MoBI 2020与2024版本的变更概要： - 纳入物种数量：MoBI 2024共纳入2493种，相较MoBI 2020的2216种。由于分类学更新与全球保护等级/《濒危物种法》保护状态变更的共同影响，2020版本中的177个物种被移除，同时新增454个物种至本2024版本。原MoBI 2020包含的所有分类类群均被纳入2024版本，此外还新增了数个独居蜂属类群。 - 尺度变更：我们将所有MoBI产品的分辨率从990米提升至330米。由于分辨率提升，建议在对MoBI 2020与MoBI 2024版本进行直接比较时保持谨慎。如需下载图层包格式的数据，请访问此处。