California Native Plant Society

Rare Plant Program

The California Natural Diversity Database: California's Natural Heritage Program

Roxanne L. Bittman (from CNPS Inventory, 6th Edition, 2001)

The California Natural Diversity Database (CNDDB) is part of the Habitat Conservation Planning Division of the California Department of Fish and Game, and serves to inventory the locations of the state's rarest species and natural communities. Its goal is to help conserve California's biotic diversity by providing government agencies and the private sector with information so that wise land?use decisions and resource management can occur. The CNDDB is used to identify important natural areas, and also in project planning to avoid conflicts between environmental and development interests.

Using the CNDDB to Protect Rare Plant Populations 

There are many potential applications for the CNDDB records, but those concerning land development and environmental impact review are especially important. Rapid population growth and economic expansion need to be carefully reconciled with protection of California's resource base, and project developers must often consult with the CNDDB. The developer, usually with a specific geographic location of concern, requests information on the rare plants, animals, and natural communities that may occur at that location. CNDDB data, along with data from the CNPS Inventory, thus often constitute the first cut for developers or their consultants when devising a "potentials list" of special plants, animals, and communities that may occur in a project area. This is then followed by surveys for rare species and natural communities during the appropriate time of year by qualified biologists and ecologists.

The impacts on the biological resources of this proposed project area can then be evaluated by the developers' consultants, and issues of project feasibility, cost, and mitigation can be adequately addressed. If such information is obtained early in the planning process, needless conflicts, stalled permits, and the costs of project delay may all be avoided. It should be emphasized that acquisition of CNDDB data is not in itself sufficient to satisfy the requirements of the California Environmental Quality Act. Biological surveys, performed by qualified personnel at the appropriate time of year, are essential to document what is actually present on the parcel of concern (see Guidelines for Assessing Effects of Proposed Projects on Rare, Threatened, and Endangered Plants and Natural Communities).

Citizens or conservation groups interested in the protection of biological diversity in California are also encouraged to use the CNDDB. Customers can access the CNDDB in a number of ways, depending on their needs. The most popular way is by purchasing RareFind (now in its second edition), a menu-based program which allows access to all of the textual information in the CNDDB. Data can be accessed by searching for individual counties, quads, or taxa, and various reports are possible. Another common way to acquire CNDDB data is to request the textual and graphic information for a particular area (a quad, for example). These data are presented as a vellum overlay to a specific topographic map along with an accompanying text report on the rare elements appearing on the overlay. Simple lists of rare plants and their status are available from our web site ( or as hard copy by telephoning (916) 324-3812.

CNDDB information is available on a cost reimbursement basis. The most common users are conservationists, state and federal agencies, consultants, and researchers. CNDDB data are half-price for conservation organizations and other non-profit groups. Often CNDDB reports are offered free to citizens interested in reporting back to us regarding the current condition of populations or stands of rare elements.

In general, CNDDB data for plants are made available to CNPS chapters on a yearly basis. Some CNPS chapters receive RareFind, and others receive written reports, along with copies of vellum overlays at the 1:100,000 scale. You may request information for local areas by contacting us at the address below. Most requests take about two weeks to process. Requests for large amounts of data or special products may require special processing; contact the CNDDB for details.

Updating the Database: Contributions from the Field 

As of May 2000, the CNDDB computer files contained approximately 17,553 records on 1,209 plants (out of 1,784 plants on the Special Plants list), 16,094 records on 437 animals (out of 651 animals on the Special Animals list) and 2,635 records on 147 of our most endangered natural communities (out of the approximately 619 rare natural communities on the list). Biologists throughout the state have contributed to collection of these data which describe the locations, ecology, and status of these elements. The original data set for plants largely stemmed from herbarium records from institutions such as the University of California Berkeley, California Academy of Sciences, U.C. Riverside, Rancho Santa Ana Botanic Garden, Humboldt State University, and others. Recent, updated plant location data comes largely from surveys done by members of the California Native Plant Society, agency biologists, and consultants. Data contributions are strongly encouraged.

To contribute information on population fluctuations, new locations, and habitat integrity, we encourage you to use the California Native Species Field Survey Form ( We have new and improved versions of the forms for both species and natural communities available to all. Attaching a location map to the form is essential to ensure that we accurately enter the information into the computer.

Roxanne Bittman is the Botanist at the California Natural Diversity Database, Department of Fish and Game, 1416 Ninth St., 12th Floor, Sacramento, CA 95814.

Additional Information

Department of Fish and Game - web site

Natural Diversity Database - web site

Biogeographic Data Branch


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