Southern Mountain Yellow-Legged Frog Range - CWHR A044 [ds613]

CWHR species range datasets represent the maximum current geographic extent of each species within California. Ranges were originally delineated at a scale of 1:5,000,000 by species-level experts more than 30 years ago and have gradually been revised at a scale of 1:1,000,000. Species occurrence data are used in defining species ranges, but range polygons may extend beyond the limits of extant occurrence data for a particular species. When drawing range boundaries, CDFW seeks to err on the side of commission rather than omission. This means that CDFW may include areas within a range based on expert knowledge or other available information, despite an absence of confirmed occurrences, which may be due to a lack of survey effort. The degree to which a range polygon is extended beyond occurrence data will vary among species, depending upon each species’ vagility, dispersal patterns, and other ecological and life history factors. The boundary line of a range polygon is drawn with consideration of these factors and is aligned with standardized boundaries including watersheds (NHD), ecoregions (USDA), or other ecologically meaningful delineations such as elevation contour lines. While CWHR ranges are meant to represent the current range, once an area has been designated as part of a species’ range in CWHR, it will remain part of the range even if there have been no documented occurrences within recent decades. An area is not removed from the range polygon unless experts indicate that it has not been occupied for a number of years after repeated surveys or is deemed no longer suitable and unlikely to be recolonized. It is important to note that range polygons typically contain areas in which a species is not expected to be found due to the patchy configuration of suitable habitat within a species’ range. In this regard, range polygons are coarse generalizations of where a species may be found. This data is available for download from the CDFW website: https://www.wildlife.ca.gov/Data/CWHR. The N CA DPS range was adopted from the Interagency Conservation Strategy for Mountain Yellow-Legged Frogs in the Sierra Nevada: https://www.fws.gov/sites/default/files/documents/Mountain-Yellow-Legged-Frog-Conservation-Strategy.pdf The following data sources were collated for the purposes of range mapping and species habitat modeling by RADMAP. Each focal taxon’s location data was extracted (when applicable) from the following list of sources. BIOS datasets are bracketed with their “ds” numbers and can be located on CDFW’s BIOS viewer: https://wildlife.ca.gov/Data/BIOS. California Natural Diversity Database, Terrestrial Species Monitoring [ds2826], North American Bat Monitoring Data Portal, VertNet, Breeding Bird Survey, Wildlife Insights, eBird, iNaturalist, other available CDFW or partner data.CWHR物种分布数据集（CWHR species range datasets）代表加利福尼亚州内各物种当前的最大地理分布范围。该分布范围最初于30多年前由物种专家以1:500万比例尺划定，后续逐步以1:100万比例尺完成修订。物种分布范围的划定会参考物种出现数据，但分布多边形（range polygons）可能会超出某一物种的现存出现数据边界。加州鱼类与野生动物部（California Department of Fish and Wildlife, CDFW）在绘制分布边界时，秉持宁多勿漏的原则：即便因调查力度不足而未获得确认的物种出现记录，专家组也可基于专业知识或其他可用信息，将相关区域纳入物种分布范围。分布多边形超出现存出现数据的程度因物种而异，取决于各物种的移动扩散能力、扩散模式以及其他生态与生活史特征。分布多边形的边界绘制会综合考量上述因素，并与标准化边界对齐，包括流域（National Hydrography Dataset, NHD）、生态区（United States Department of Agriculture, USDA）或其他具有生态意义的划分方式（如海拔等高线）。尽管CWHR分布范围旨在反映物种当前的分布，但某一区域一旦被纳入CWHR的物种分布范围，即便近数十年内未出现相关记录，仍会保留在分布多边形中。除非专家组经多次调查确认该区域已多年未被物种占据，或认定其不再适宜物种栖息且不太可能被重新定居，否则不会将其从分布范围内移除。需要注意的是，由于物种分布范围内适宜栖息地呈斑块状分布，分布多边形通常会包含一些理论上不会有物种出现的区域，因此其本质是对物种可能分布区域的粗略概括。该数据集可从加州鱼类与野生动物部官网下载：https://www.wildlife.ca.gov/Data/CWHR。内华达山脉山地黄腿蛙跨部门保护策略中的北加州DPS分布范围被纳入本数据集，来源链接为：https://www.fws.gov/sites/default/files/documents/Mountain-Yellow-Legged-Frog-Conservation-Strategy.pdf。本次分布范围绘制与物种栖息地建模工作由RADMAP完成，各目标类群的位置数据（如适用）从以下来源提取：BIOS数据集（BIOS datasets）以其"ds"编号标注，可通过加州鱼类与野生动物部的BIOS浏览器访问：https://wildlife.ca.gov/Data/BIOS。具体数据源包括：加州自然多样性数据库、陆地物种监测[ds2826]、北美蝙蝠监测数据门户、VertNet、繁殖鸟类调查（Breeding Bird Survey）、Wildlife Insights、eBird、iNaturalist，以及其他可获取的加州鱼类与野生动物部或合作方数据。