Smith's Black-Headed Snake Range - CWHR R069 [ds1775]

Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for California's wildlife. The CWHR System was developed to support habitat conservation and management, land use planning, impact assessment, education, and research involving terrestrial vertebrates in California. CWHR contains information on life history, management status, geographic distribution, and habitat relationships for wildlife species known to occur regularly in California. Range maps represent the maximum, current geographic extent of each species within California. They were originally delineated at a scale of 1:5,000,000 by species-level experts and have gradually been revised at a scale of 1:1,000,000. For more information about CWHR, visit the CWHR webpage (https://www.wildlife.ca.gov/Data/CWHR). The webpage provides links to download CWHR data and user documents such as a look up table of available range maps including species code, species name, and range map revision history; a full set of CWHR GIS data; .pdf files of each range map or species life history accounts; and a User Guide.

CWHR分布范围图矢量数据集是加州野生动物栖息地关系（California Wildlife Habitat Relationships, CWHR）的组成部分之一，该系统是一套面向加州野生动物的综合信息系统与预测模型。CWHR系统的开发初衷是为涉及加州陆生脊椎动物的栖息地保护与管理、土地利用规划、环境影响评价、科普教育及科学研究提供支撑。该系统收录了已知定期栖息于加州的野生动物物种的生活史、管理现状、地理分布及栖息地关联性等信息。分布范围图展示了各物种在加州境内当前的最大地理分布范围，最初由各物种领域专家以1:500万比例尺绘制，并已逐步更新为1:100万比例尺的修订版本。如需了解CWHR的更多信息，可访问其官方网页（https://www.wildlife.ca.gov/Data/CWHR）。该网页提供了CWHR数据与各类用户文档的下载链接，涵盖：包含物种代码、物种名称及分布范围图修订历史的可用分布范围图检索表；全套CWHR地理信息系统（Geographic Information System, GIS）数据；各分布范围图或物种生活史说明的PDF文件；以及一份官方用户指南。