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State Reports - California

Land cover and land management mapping for the California Gap Analysis Project (CA-GAP) have been virtually completed. The California Department of Fish and Game is helping with refining the interpretation of habitat types from the land cover data and with final predictions of vertebrate species distributions. Attention has been shifted more towards data analysis and distribution of the database. The current plan is to distribute the database and report on both the World Wide Web and CD-ROM. In addition, an interactive atlas on CD-ROM with a graphical user interface built on ESRI’s ArcView software is being developed. This product will allow users without GIS experience to query the CA-GAP database about the distribution of the state’s biota and associated land management. The Universal Resource Locator address (URL) for the CA-GAP web site is http://www.biogeog.ucsb.edu/gap/gap.html, which will provide access to GAP data and the report once they are completed. The Department of Fish and Game plans to take over the long-term maintenance and distribution of CA-GAP data.

CA-GAP staff, in collaboration with researchers from the Department of Geography at the University of California-Santa Barbara and the National Center for Ecological Analysis and Synthesis, have continued to work on techniques for using GAP data to identify efficient networks of biodiversity management areas. These techniques, adapted from the field of operations research, address the conservation principles of efficiency, representation, irreplaceability, flexibility, and suitability. Our first entry in this arena was to reformulate the iterative, rule-based procedures developed in Australia into a maximal covering location problem (Church et al. 1996), which maximizes the number of species represented in a fixed number of sites. A version of this optimization modeling approach has since been integrated completely into the ARC/INFO environment (Gerrard et al. in review). We also outlined a protocol for the U. S. Forest Service that includes a variation of this model using GAP data from which to select candidate sites for new Research Natural Areas (Moritz et al. 1997; Stoms et al. in review). We developed a land allocation model that balances the efficiency of the network with the suitability of the selected sites while filling the gaps to some prescribed percentage target level (Davis et al. 1996). CA-GAP is currently working with The Nature Conservancy to adapt this model to help them identify their regional conservation portfolio. The prototype is being applied in the Columbia Plateau ecoregion and was presented at this year’s Ecological Society of America meeting. An overview of our reserve selection research was presented at the Society for Conservation Biology meeting in Victoria, B.C.

In the past year, one Ph.D. dissertation (Thomas 1996) and one master’s thesis (Thorne 1997) were completed, representing GAP-related research in the Mojave Desert and Northwestern California regions, respectively. Several peer-reviewed articles relating to CA-GAP were published, accepted for publication, or submitted since the last newsletter. The final report of the Sierra Nevada Ecosystem Project was submitted to Congress. The report contains a chapter on a Gap Analysis of plant communities (Davis and Stoms 1996) and one on an approach for selecting an optimal system of biodiversity management areas to fill conservation gaps (Davis et al. 1996).

Literature Cited

Church, R. L., D. M. Stoms, and F. W. Davis. 1996. Reserve selection as a maximal covering location problem. Biological Conservation 76: 105-112.

Davis, F. W., and D. M. Stoms. 1996. Sierran vegetation: A gap analysis. Pages 671-689 in Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options. Davis: University of California, Centers for Water and Wildlands Resources.

Davis, F. W., D. M. Stoms, R. L. Church, W. J. Okin, and K. N. Johnson. 1996. Selecting biodiversity management areas. Pages 1503-1528 in Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options. Davis: University of California, Centers for Water and Wildlands Resources.

Gerrard, R. A., R. L. Church, D. M. Stoms, and F. W. Davis. Selecting conservation reserves using species covering models: Adapting the ARC/INFO GIS. Submitted to Transactions in GIS.

Moritz, M., D. M. Stoms, M. I. Borchert, and F. W. Davis. 1997. A proposed protocol for identifying potential Research Natural Areas with Gap Analysis data. Proceedings of the 17th Annual ESRI User Conference. CD-ROM and WWW. In press.

Stoms, D. M., M. I. Borchert, M. A. Moritz, F. W. Davis, and R. L. Church. A systematic process for siting Research Natural Areas. Submitted to Natural Areas Journal.

Thomas, K. A. 1996. Vegetation and Floristic Diversity in the Mojave Desert of California: A Regional Conservation Evaluation. Ph.D. dissertation, University of California, Santa Barbara.

Thorne, J. H. 1997. Gap Analysis: The vegetation of Northwestern California. Masters thesis, Department of Geography, University of California, Santa Barbara.

Project Information

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