Wildlife Habitats - California Wildlife Habitat Relationships System

About the CWHR Habitat Classification Scheme

The CWHR habitat classification scheme was developed to provide a systematic method for describing how the constituent stage classes and structures support California's regularly-occurring birds, mammals, reptiles and amphibians. When first published in 1988, the classification scheme had 53 habitats. These habitats, except the non-vegetated Barren habitat, are described in detail in the CWHR publication entitled:

A Guide to Wildlife Habitats of California. 1988.
Edited by Kenneth E. Mayer and William F. Laudenslayer, Jr.
State of California, Resources Agency,
Department of Fish and Game
Sacramento, CA. 166 pp.

The entire original publication is available online with updates (see below).

At present, there are 59 wildlife habitats in the CWHR System: 27 tree, 12 shrub, 6 herbaceous, 4 aquatic, 8 agricultural, 1 developed, and 1 non-vegetated (download Habitat Range shapefiles (.zip)). Please note: the 59 habitats described below were designed for use with a predictive model for terrestrial vertebrate wildlife species. They do not represent a comprehensive classification scheme for the conservation and mapping of California's terrestrial vegetation* or its marine and estuarine habitats**.

• Stages are defined for virtually all habitats. A stage is a combination of size and cover class for tree-dominated habitats, age and cover class for shrub habitats, height and cover class for herb habitats, and depth and substrate for aquatic habitats. A field sampling protocol is well-established for determining stages in all vegetated habitats.
• Special habitat elements are also defined. They include live and decadent vegetation elements such as snags, physical elements such as banks and burrows, aquatic elements, vegetative and animal diet elements and human-made elements.

The predictive model for each species has expert-applied suitability ratings for three life-requisites – breeding, cover and feeding. For each species, each habitat stage is rated as high, medium, low or unsuitable for each of these life requirements. Each special habitat element is also assessed as essential, secondarily essential, preferred or not rated for the species.

* Notes on Classification and Mapping of Terrestrial Vegetation in California

• Information on classification and mapping of terrestrial vegetation is available from the Vegetation Classification and Mapping Program (VegCAMP), CDFW Biogeographic Data Branch.
• Field sampling for CWHR habitat stages has been incorporated into the California Native Plant Society (CNPS) Rapid Assessment Protocol, to increase the utility of the resulting vegetation maps for wildlife modeling and conservation. Information and links to field forms are available on the CNPS website(opens in new tab).
• Crosswalks to the CWHR habitat classification scheme are included in all of California's major vegetation and land cover mapping efforts.

** Notes on Classification of Marine and Estuarine Habitats in California

• A classification scheme for the conservation and management of marine and estuarine habitats was developed in cooperation with the CWHR Program in 2002. It includes descriptions for 22 marine and 19 estuarine habitats. At present, it does not include suitability ratings to habitat stages or special habitat elements for the terrestrial amphibians, reptiles, birds and mammals currently in the CWHR System.
• The new classification includes crosswalks to other important, recent classifications regarding coastal waters. Included are crosswalks to Wetlands of the Central and Southern California Coast and Coastal Watersheds; a methodology for their classification and description (Ferren et al., 1996), Baylands Ecosystem Habitat Goals: a report of habitat recommendations (U.S. Environmental Protection Agency, 1999), A classification scheme for deep sea floor habitats (Greene et al., 1999), and Wildlife-habitat relationships in Oregon and Washington (Johnson and O'Neil, 2001). Also included are crosswalks to a national scheme for marine and estuarine ecosystems and habitat classification published by the National Oceanic and Atmospheric Administration (NOAA) in 2002 and a classification for habitats of the Channel Islands drafted in 2000 by the Channel Island National Marine Sanctuary (CINMS).

Revision to Marine and Estuarine Habitats of the California Wildlife Habitat Relationships System (2002) (PDF)(opens in new tab)

A Guide to Wildlife Habitats of California (1988)

Habitat Types

Jump to:

• Tree Dominated Habitats
• Shrub Dominated Habitats
• Herbaceous Dominated Habitats
• Aquatic Habitats
• Developed Habitats
• Non-vegetated Habitats

Tree Dominated Habitats

Shrub Dominated Habitats

Herbaceous Dominated Habitats

Aquatic Habitats

See also: "Notes on Classification of Marine and Estuarine Habitats"

Developed Habitats

Non-vegetated Habitats