Marbled Murrelet Range - CWHR B240 [ds930]

The species range dataset represents the generalized geographic area within which the species is expected to regularly occur within California, without consideration of specific habitat requirements. Generally, range map boundaries are based on mapped species occurrence locations and expert knowledge and aligned with ecologically relevant units such as ecoregions or watersheds. The California Wildlife Habitat Relationship (CWHR) ranges have been developed over three decades and vary in age of last update. The date of last update can be found in the CWHR Revision Tracking Table at https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=115517.

GIS vector datasets representing species ranges are one component of the CWHR system. This system includes a web application that supplies information on California’s terrestrial vertebrates and the habitats upon which they depend, supports user queries, and houses spatial data on habitats and 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 that occur in California. CWHR species range datasets represent the maximum current geographic extent of regularly occurring terrestrial vertebrate species within California. These range datasets are used to generate a tabular database of species locations by county, ecoregion, and several other jurisdictional delineations to inform the CWHR system. This enables users to query for wildlife species meeting a set of location and habitat conditions. The species range datasets are also used by many groups to assist with development of biological surveys, and within CDFW to support species richness assessments for statewide conservation planning.

For more information about the CWHR system, visit the CWHR Homepage: https://www.wildlife.ca.gov/Data/CWHR.