Turkey Vulture Predicted Habitat - CWHR B108 [ds2082]

The datasets used in the creation of the predicted Habitat Suitability models includes the CWHR range maps of Californias regularly-occurring vertebrates which were digitized as GIS layers to support the predictions of the CWHR System software. These vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model for Californias 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.The models also used the CALFIRE-FRAP compiled "best available" land cover data known as Fveg. This compilation dataset was created as a single data layer, to support the various analyses required for the Forest and Rangeland Assessment, a legislatively mandated function. These data are being updated to support on-going analyses and to prepare for the next FRAP assessment in 2015. An accurate depiction of the spatial distribution of habitat types within California is required for a variety of legislatively-mandated government functions. The California Department of Forestry and Fire Protections CALFIRE Fire and Resource Assessment Program (FRAP), in cooperation with California Department of Fish and Wildlife VegCamp program and extensive use of USDA Forest Service Region 5 Remote Sensing Laboratory (RSL) data, has compiled the "best available" land cover data available for California into a single comprehensive statewide data set. The data span a period from approximately 1990 to 2014. Typically the most current, detailed and consistent data were collected for various regions of the state. Decision rules were developed that controlled which layers were given priority in areas of overlap. Cross-walks were used to compile the various sources into the common classification scheme, the California Wildlife Habitat Relationships (CWHR) system.CWHR range data was used together with the FVEG vegetation maps and CWHR habitat suitability ranks to create Predicted Habitat Suitability maps for species. The Predicted Habitat Suitability maps show the mean habitat suitability score for the species, as defined in CWHR. CWHR defines habitat suitability as NO SUITABILITY (0), LOW (0.33), MEDIUM (0.66), or HIGH (1) for reproduction, cover, and feeding for each species in each habitat stage (habitat type, size, and density combination). The mean is the average of the reproduction, cover, and feeding scores, and can be interpreted as LOW (less than 0.34), MEDIUM (0.34-0.66), and HIGH (greater than 0.66) suitability. Note that habitat suitability ranks were developed based on habitat patch sizes >40 acres in size, and are best interpreted for habitat patches >200 acres in size. The CWHR Predicted Habitat Suitability rasters are named according to the 4 digit alpha-numeric species CWHR ID code. The CWHR Species Lookup Table contains a record for each species including its CWHR ID, scientific name, common name, and range map revision history (available for download at https://www.wildlife.ca.gov/Data/CWHR).

用于构建生境适宜性预测模型的数据集，包含加州常居脊椎动物的CWHR（California Wildlife Habitat Relationships，加州野生生物生境关系）分布范围图。此类分布图已被数字化为地理信息系统（Geographic Information System, GIS）图层，用于支撑CWHR系统软件的预测工作。这套CWHR分布范围图的矢量数据集，是加州野生生物生境关系（CWHR）系统的组成部分之一。该系统是针对加州野生生物的综合性信息系统与预测模型，其开发初衷是为涉及加州陆生脊椎动物的生境保护与管理、土地利用规划、影响评估、教育及研究工作提供支撑。CWHR系统收录了已知常栖息于加州的野生生物物种的生活史、管理现状、地理分布及生境关联等信息。分布范围图表征了各物种在加州境内当前的最大地理分布范围，最初由物种专家以1:5000000的比例尺手绘绘制，后续逐步修订为1:1000000的比例尺。如需了解CWHR系统的更多信息，请访问其官方网页（https://www.wildlife.ca.gov/Data/CWHR）。该网页提供了CWHR数据与用户文档的下载链接，包括包含物种代码、物种名称及分布范围图修订历史的可用分布图查询表、全套CWHR GIS数据、各分布图或物种生活史说明的PDF文件，以及《用户指南》。本次建模还使用了由加州林业与消防保护局（California Department of Forestry and Fire Protection, CALFIRE）森林与资源评估项目（Fire and Resource Assessment Program, FRAP）汇编的“最佳可用”土地覆盖数据，即Fveg数据集。该汇编数据集被整合为单一数据图层，以支撑《森林与牧场评估》所需的各类分析工作——这是一项法定强制要求的政府职能。目前该数据集正在进行更新，以支撑正在进行的分析工作，并为2015年的下一次FRAP评估做准备。准确刻画加州境内生境类型的空间分布，是多项法定强制政府职能的必要前提。CALFIRE的FRAP项目联合加州鱼类与野生动物局的VegCamp项目，并大量使用美国农业部（United States Department of Agriculture, USDA）林务局第五区遥感实验室（Remote Sensing Laboratory, RSL）的数据，将加州境内可获取的“最佳可用”土地覆盖数据整合为一套统一的全州综合性数据集。该数据集的时间跨度约为1990年至2014年，通常针对加州各区域采集了最新、最详细且一致性最高的数据。研究人员制定了决策规则，用于在图层重叠区域确定优先采用的数据集；同时通过分类转换对照表（cross-walks）将各类源数据整合至统一的分类体系，即加州野生生物生境关系（CWHR）系统。研究人员将CWHR分布数据与FVEG植被图、CWHR生境适宜性等级相结合，为各物种生成了预测生境适宜性分布图。此类分布图展示了该物种的平均生境适宜性得分，其定义遵循CWHR标准。CWHR将物种在各生境阶段（生境类型、面积与密度的组合）下的繁殖、栖息及觅食需求对应的生境适宜性划分为四类：无适宜性（0分）、低适宜性（0.33分）、中适宜性（0.66分）与高适宜性（1分）。平均得分为繁殖、栖息与觅食三项得分的平均值，据此可将适宜性划分为低适宜性（得分低于0.34）、中适宜性（0.34至0.66）与高适宜性（得分高于0.66）。需注意，生境适宜性等级是基于面积大于40英亩的生境斑块制定的，其最适宜的应用场景为面积大于200英亩的生境斑块。CWHR预测生境适宜性栅格数据的命名遵循4位字母数字混合的CWHR物种ID代码规则。CWHR物种查询表为每个物种提供了一条记录，包含其CWHR ID、学名、通用名及分布范围图修订历史（可在https://www.wildlife.ca.gov/Data/CWHR下载获取）。