Over the past few decades, population growth has mushroomed in Orange County, as in the rest of Southern California, with the development of new communities and the infrastructure to support them.  This growth has come at the expense of natural habitats and species in an area recognized as part of a global hotspot of biodiversity.  The loss of habitat to development created a growing list of threatened and endangered species in Southern California, presenting challenges to federal, state, and local agencies responsible for natural resource protection, as well as to developers and land use planners trying to maintain a healthy economy.  To respond to this dilemma, in 1991 the California legislature passed the Natural Community Conservation Planning (NCCP) Act to encourage a collaborative process for regional planning.  As a result of the NCCP, natural open space reserves have been set aside in the coastal and central portions of Orange County which, when combined with National Forest lands, total approximately 163,000 acres of conserved habitat—majestic peaks, chaparral and oak-studded canyons, rolling scrub- and grassland covered hills, and the remnants of formerly extensive coastal lagoons and estuaries—lands that not only contribute to the preservation of biodiversity, but to the quality of life enjoyed by all Southern Californians.  The legacy of this regional planning process continues, with the goal of protecting a green network of natural lands for wildlife habitat and open space recreation across jurisdictional boundaries in Southern California.

This report combines the results of two tasks funded under a local assistance grant from the California Department of Fish and Game (CDFG) for Multiple Species Conservation Program (MSCP) wildlife corridor monitoring:  (1) the second consecutive year of monitoring for locations in the cities of Poway and San Diego, surveyed by San Diego State University (SDSU) graduate students (contract Task D) and (2) the first year of monitoring for new transect locations established by the Conservation Biology Institute (CBI) and San Diego Tracking Team (SDTT) (contract Task A).  CBI directed both studies.  Transects at some of the Poway-San Diego monitoring stations established in 2000 (CBI 2002b) were not re-surveyed, while monitoring protocols were altered slightly based on recommendations from CBI (2002b).  Specifically, in addition to the data collected at baited track stations, the presence or absence of wildlife, as evidenced by all types of sign, was recorded along the entire length of the transect to compare the methods.  These sign surveys along the track station transects are thus similar to surveys conducted by the SDTT.

There is increasing interest in the effects of urbanization on natural systems. Among the variety of observed effects, urbanization has long been recognized as affecting hydrological characteristics of streams and rivers. Given the close coupling of stream hydrologic characteristics and riparian plant species ecology, we examined the effects of watershed urbanization on riparian vegetation communities via alterations in the hydrologic regime of a coastal southern California riparian system. These coastal river systems in southern California have received little attention in the literature.

The mission of the Volcan Mountain Preserve Foundation (VMPF) is conservation and stewardship of the majestic 15-mile long Volcan Mountains complex, situated within the Peninsular Ranges of Southern California (Figure 1).  The emphasis of VMPF is conserving natural habitats and the species they support, maintaining wilderness values and connections to adjacent open space, preserving archaeological sites, and encouraging natural history-based research and education.

Land conservation in the Volcan Mountains began in 1989; since that time, over 9,000 acres of the former Rutherford Ranch on Volcan Mountain have been acquired by public agencies and non-governmental organizations as protected open space, complemented by conservation of tens of thousands of acres of surrounding lands (Figure 2).  However, approximately 1,800 acres of Rutherford Ranch in the heart of the range, between these conserved lands and the Santa Ysabel Indian Reservation on the western flank of the mountain, lie unprotected and are currently threatened with development of estate lots.

VMPF requested that The Nature Conservancy (TNC) and Conservation Biology Institute (CBI) prepare a brief case statement that would provide the basis from which it can develop a focused conservation strategic plan.  This case statement describes the landscape that is the inspiration for the VMPF, with a focus on the privately held portions of Rutherford Ranch, by identifying regional conservation values and potential partners for conservation of these values within the context of existing opportunities.

The Sierra Nevada, John Muir’s Range of Light, is a state and national treasure, valued for its scenic beauty, rich biodiversity, ancient forests, unparalleled recreational opportunities, and commercial timber and water resources.  The Sierra Nevada supports over 60% of California’s vertebrate species and over half of its plant species.  For its size, it is the most floristically diverse area in North America.  The Sierra supports 50 million recreational visitor days each year, and its watersheds deliver 65% of the water supply for California residents.

The Global 200 Strategy amitiously seeks to conserve the variety of species, ecosystems, and ecological and evolutionary processes that sustain life on earth.  Toward this end, the World Wildlife Fund hs identified over 200 ecoregions (Global 200) recognized for their high conservation priority, and calls for concentrated conservation planning in these regions.  Not surprisingly, of the wide array of ecosystem types included in the Global 200, forest ecosystems constitute the majority.  In fact, 87 of the 136 terrestrial ecoregions fall into one of five Major Habitat Types – Tropical and Subtropical Moist Brodleaf Forests, Tropical Dry Forests, Tropical and Sustropical Conifer Forests, Temperate Conifer and Broadleaf Forests, and Boreal Forests and Taiga.

The purpose of this report is threefold: (1) discuss the concept of forest restoration from a conservation biology perspective; (2) outline the ecological characteristics, technical constraints, socio-political and economic influences, and overall restoration principles relevant to the Global 200 major habitat types and associated realms; and (3) place forest restoration within the larger context of worldwide forest conservation.

The critically endangered Pacific pocket mouse (Perognathus longimembris pacificus), feared extinct for over 20 years, was “rediscovered” in 1993 and is now documented at four sites in Orange and San Diego Counties, California. Only one of these sites is considered large enough to be potentially self-sustaining without active intervention. In 1998, I gathered a team of biologists to initiate several research tasks in support of recovery planning for the species. The PPM Studies Team quickly determined that species recovery would require active translocations or reintroductions to establish new populations, but that we knew too little about the biology of P. l. pacificus and the availability of translocation receiver sites to design such a program. Recovery research from 1998 to 2000 therefore focused on (1) a systematic search for potential translocation receiver sites; (2) laboratory and field studies on non-listed, surrogate subspecies (P. l. longimembris and P. l. bangsi) to gain biological insights and perfect study methods; (3) studies on the historic and extant genetic diversity of P. l. pacificus; and (4) experimental habitat manipulations to increase P. l. pacificus populations. Using existing geographic information system (GIS) data, we identified sites throughout the historic range that might have appropriate soils and vegetation to support translocated P. l. pacificus. Reconnaissance surveys of habitat value were completed in all large areas of potential habitat identified by the model. Those sites having the highest habitat potential are being studied with more detailed and quantitative field analyses. The surrogate studies helped us design individual marking and monitoring methods and will be used to test translocation methods before applying them to P. l. pacificus. Genetic results suggest that P. l. pacificus populations were naturally fairly isolated from one another prior to modern development, that genetic diversity will continue to erode in the small populations that remain, and that individuals from extant populations could probably be mixed if maximizing genetic diversity in any newly established populations is an important recovery goal. Local populations should be increased in situ before they can supply donor animals for translocations. Experimental habitat management (shrub thinning) at one occupied site yielded a short-term, positive, behavioral response of mice to thinned habitat plots. However, the overall population seems to be in decline, and long-term population responses to habitat manipulations are not yet evident. The approach of the PPM Study Team has been to proceed cautiously and scientifically to obtain critical information and to design a translocation program, but we are prepared to recommend swift action to prevent extinction despite “insufficient data.” At this point, political and economic obstacles to species recovery seem larger than obstacles presented by scientific uncertainty.

Spencer, W.D. 2005. Recovery research for the endangered Pacific pocket mouse: An overview of collaborative studies. In B.E. Kus and J.L. Beyers, technical coordinators. Planning for Biodiversity: Bringing Research and Management Together: Proceedings of a Symposium for the South Coast Ecoregion. Gen. Tech. Rep. PSW-GTR-195. Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture, Albany, CA: 274pp.

Tejon Ranch is one of California’s most precious natural areas—a haven for rare and endangered species, a sanctuary for the soul of ancient California, a treasure that, through the years, has not escaped the wonderment of ranchers, hunters, wildlife enthusiasts, and scientists. This is a place through which thousands of people drive daily, but few have really seen; where one can visualize the dramatic geologic processes that shaped California’s landscape and influenced the evolutionary history of California’s diverse flora and fauna. In this place, California condors still fly, centuries-old oaks still flourish, and streams are born. Perhaps most remarkably, virtues of this place have not yet been compromised by the urban sprawl that is rapidly devouring so much of California’s natural landscape.

Tejon Ranch, 270,000 acres of southern Kern and northern Los Angeles counties, is the largest, contiguous, privately owned property in California.  Owners of the Ranch are currently planning large-scale residential and industrial developments in what is now a largely undeveloped and natural landscape. Concerned that these development plans might severely compromise the Ranch’s ecological integrity before the public has had an opportunity to understand its significance, Environment Now and a coalition of environmental groups commissioned the Conservation Biology Institute to assess the regional and statewide value of Tejon Ranch for conservation of biological diversity. Through the course of this assessment, we have come to recognize what others have already suggested—that Tejon Ranch is truly one of California’s most priceless natural areas, unparalleled in its diversity of natural resources and its importance to conservation, and meeting all of the State’s criteria for a priority conservation target.

This report shares our synthesis of publicly available information—documenting the biogeographic importance of the Tejon Ranch region, revealing the values of the region’s natural resources, and identifying factors that threaten these values. This report does not advocate any specific open space design, but rather it illuminates the extraordinary values and regionally under-protected resources of the Ranch so that the public and decision-makers are fully aware of their importance in future land planning decisions. We hope that this information will be used as a basis for comprehensive, rather than piecemeal, land use planning of Tejon Ranch.

Tejon Ranch supports a multitude of irreplaceable biological resources, and the melding of these resources in one large, intact landscape makes the Ranch a regionally significant conservation target. This report evaluates the distribution of conservation values on Tejon Ranch, as an incremental step towards developing a regional reserve design.

We used publicly available data and science-based conservation principles to describe and map selected conservation values for Tejon Ranch. Our assessment demonstrates that, although different areas of the Ranch support different sets of conservation values, virtually all areas of the Ranch support one or more sets of values. To spatially describe the distribution of these values on Tejon Ranch, we identified four landscape units that differentially support the conservation values considered in our analysis:

Reserve designs for Tejon Ranch must, at a minimum, capture these values while ensuring the maintenance and management of ecological processes within and between landscape units. Similarly, conservation planning must ensure integration and connection of these landscape units with others in the region, along with a regional plan for long-term management and biological monitoring. Without careful and comprehensive consideration, land use plans for Tejon Ranch could irretrievably alter the biological functions and values of this keystone landscape.

The 270,750-acre Tejon Ranch is the largest contiguous tract of privately owned land in California. In addition to its outstanding core biological resource values, the Ranch represents a biogeographic crossroads of many Californias—the Sierra Nevada, the PacificCoast, the Mojave Desert, and the Great Central Valley. It represents the last intact connection among these ecoregions for numerous plants and animals that cannot cross water, intensive agriculture, or urban development. Unfortunately, it is also currently subject to development proposals that threaten to destroy the ecological integrity of this remarkable legacy.

Given the size, integrity, and geographic context of Tejon Ranch, and the regional significance of its resources, virtually all of Tejon Ranch merits protection for future generations.Therefore, we strongly urge a regional conservation solution for Tejon Ranch that is worthy of its irreplaceable resource values, cultural significance, and heritage of the citizens of California. It is in this spirit that we propose a wildland reserve design for the Ranch that captures the broad array of landscape functions and conservation values that it supports.