Science
The Tejon Ranch Conservancy’s Science Program is guided by our core values:
- Understanding and applying the best available conservation science is our foundation for stewardship, restoration and protection of native biodiversity and ecosystem values.
- The Tejon Ranch Conservancy is committed to maintaining our independence to help to ensure the integrity of our actions.
- The Tejon Ranch Conservancy was born out of an extraordinary collaboration. We seek to continue in that spirit by proactively seeking partnerships on key elements of our work.
- The Tejon Ranch Conservancy is committed to a culture of openness in our activities and our decisions.
All of our activities are considered in light of our mission to preserve, enhance, and restore the native biodiversity and ecosystem values of Tejon Ranch and the Tehachapi Range for the benefit of California’s future generations. Conservation of Tejon Ranch is forever, so we consider ourselves the temporary custodians of this mission. We strive to implement rigorous research and management projects to inform our current stewardship of Tejon Ranch and to develop a baseline understanding of the Ranch’s natural resources for future generations of Conservancy stewards. The scale and complexity of the conserved lands compels collaboration with strong partners from academia, non-governmental organizations, government agencies, and the general public.
We make a concerted attempt to provide meaningful research and public access, but we know that not everyone will be able to explore Tejon Ranch, as we have had the good fortune to. Thus, the interactive map below provides glimpses into some of the resources found on the Ranch, and the links on this page to research, citizen science, and other resources will provide a variety of additional information about Tejon Ranch.
Tejon Ranch is located at the intersection of four major ecological regions, Great Central Valley, Sierra Nevada, Mojave Desert, and Southwestern California. Thus, the diversity of plants and animals found on Tejon Ranch reflects its position at what has been termed a biogeographic crossroads, where species unique to each of these regions can be found together on the Ranch.
The map above provides photos taken at various locations on Tejon Ranch to illustrate the diversity of habitats and species that can be found here.
Conservation Significance of Tejon Ranch:
The Tejon Ranch, at 270,000 acres, is the largest contiguous private property in California. Tejon Ranch straddles the Tehachapi Mountains, and lies at the convergence of four major ecological regions: Great Central Valley, Sierra Nevada, Mojave Desert, and Southwestern California. Thus, the diversity of plants and animals found on Tejon Ranch reflects its position at what has been termed a biogeographic crossroads, where species unique to each of these regions can be found together on the Ranch. Tejon Ranch appears to be a hotspot of evolution, where a large number of different species and subspecies have evolved over time. Tejon Ranch is a largely roadless, biological core area with high habitat integrity and intact, functioning watersheds. The Ranch is also characterized by a significant amount of topographic complexity – over 6,000 feet of elevation change, major north-south and east-west trending canyons, and a well distributed diversity of slopes and aspects – thereby providing landscape resilience and a potential refuge for species in the face of climate change.
The east-west trending Tehachapi Mountain Range is the spine of regional landscape linkage between the Coast/Transverse Ranges to the west and the Sierra Nevada to the east. Tejon Ranch’s location at the center of this continentally significant linkage contributes immeasurably to its conservation significance. This linkage includes the last grassland corridor around agricultural lands in the southern San Joaquin Valley, oak and pinyon-juniper woodlands that connect to the west and east slopes of the Sierra Nevada respectively, and “sky islands” of conifer habitat connecting the more extensive conifer forests in the adjacent Transverse Range and Sierra Nevada.
The elevational gradients combined with the ecoregional convergence exhibited in this region contribute to its outstanding evolutionary connectivity. The region is known by taxonomists as a notably dynamic area for contact between sub-specific forms, races and morphs of numerous taxa. Intraspecific diversity is thought to contribute to the resiliency of species in the face of environmental stochasticity and climate change. The evolutionary processes that create this diversity is worthy of conservation in its own right.
Significant public and private conservation investments have been made in this Tehachapi linkage, including the Los Padres and Sequoia National Forests, the Wildlands Conservancy’s Windwolves Preserve, Bittercreek National Wildlife Refuge, Carrizo Plains National Monument and other Bureau of Land Management administered lands, as well as private lands protected from development via current use tax incentives (Williamson Act) and conservation easements. The conserved lands on Tejon Ranch represent a major contribution towards securing this continental-scale linkage, and create leverage for additional conservation to complete this statewide conservation priority.
Tejon Ranch supports a very high diversity of regionally significant vegetation communities. Notable examples include:
• The last remaining grasslands in this portion of the southern San Joaquin Valley, which support abundant native forb and bulb species.
• Perhaps some of the most intact and species rich oak woodlands left in California – with at least 12 oak taxa known from the Ranch.
• The western-most stands of Joshua tree woodlands in the U.S.
• Extensive native-dominated Mojave Desert grasslands that exhibit spectacular native wildflower displays in the spring.
• Sky islands of white fir and incense cedar forests.
• Highly diverse and intact riparian communities on both the San Joaquin Valley and Mojave Desert sides of the Ranch, many along perennial streams, including beautiful examples of California sycamore alluvial woodlands.
Tejon Ranch supports over two dozen different major vegetation communities, representing over 60% of the vegetation communities in the region. Given its unique biogeographic position, variable topography and diverse geologic origins, many distinct associations of vegetation species are expected with further investigation. Thus, the conservation lands at Tejon Ranch capture a good representation of the biodiversity of the region, and provide a unique opportunity to conserve grasslands and oak woodlands that are under-protected in the region.
• Within the 240,000-acre potential conservation area of the Ranch, over 84,000 acres of various oak woodlands exist, representing a substantial increase in the conservation of these habitats in the region.
• Likewise, nearly 100,000 acres of grasslands are present in the potential conservation area, including over 10,000 acres of native grasslands and tens of thousands of acres more supporting substantial populations of native forb and bulb species.
• “Sky islands” of conifer forest, primarily white fir, in the conserved lands on the Ranch are a regionally significant community serving to connect high elevation conifer forests in the adjacent Sierra Madre, San Emigdio Mountains and Sierra Nevada.
• Numerous special status plant species are found in the conserved lands on Tejon Ranch, including striped adobe lily (State Threatened), Bakersfield cactus (Federally Endangered), Tehachapi buckwheat (CNPS List 1B.1), (Vasek’s clarkia (CNPS List 1B.1), Tejon poppy (CNPS List 1B.1), Comanche Point layia (CNPS List 1B.1), Piute Mountain’s navarretia (CNPS List 1B.1), Fort Tejon woolly sunflower (CNPS List 1B.1), alkali mariposa lily (CNPS List 1B.2), calico monkeyflower (CNPS List 1B.2), Palmer’s mariposa lily (CNPS List 1B.2), red rock tarplant (CNPS List 1B.2), San Bernardino aster (CNPS List 1B.2), and flax-like monardella (CNPS List 1B.3). Many of these special status plants are known only from Tejon Ranch or the centers of their distributions are on the Ranch.
The conserved lands of Tejon Ranch provide high quality habitat for diverse wildlife.
• Perhaps the Ranch’s most iconic species is the endangered California condor. The high country of the Ranch provides important condor foraging and roosting habitat. Recent Global Positioning Satellite tagged condors have exhibited very high utilization of the conserved lands.
• The extensive oak woodlands on Tejon Ranch also support extensive high quality habitat for cavity nesting birds, such as acorn woodpecker, purple martin (California Species of Special Concern) and California spotted owl (California Species of Special Concern), and many raptor species such as golden eagle (California Fully Protected Species and California Species of Special Concern), red-tailed hawk and Cooper’s hawk (California Species of Special Concern). In fact, the conservation value of the oak woodlands on the north slope of Tejon Ranch is recognized by their inclusion within Audubon California’s Tehachapi Mountains Important Bird Area, and the Conservancy’s first Christmas Bird Count produced the highest count of golden eagles in the U.S.
• The San Joaquin Valley grasslands on the Ranch are known to support blunt-nosed leopard lizard (Federally and State-Endangered), San Joaquin kit fox (Federally Endangered and State Threatened), San Joaquin whipsnake (California Species of Special Concern), burrowing owl (California Species of Special Concern), California horned lark (California Species of Special Concern), and loggerhead shrike (California Species of Special Concern), as well as wintering populations of mountain plover (California Species of Special Concern), long-billed curlew, ferruginous hawk, and prairie falcon.
• Tehachapi pocket mouse (California Species of Special Concern), burrowing owl, wintering populations of mountain plover and long-billed curlew, and a reintroduced population of pronghorn are found in the Antelope Valley portion of Tejon Ranch.
The Tehachapis sit in the middle of an important, but poorly understood migratory corridor. Canyons on the San Joaquin Valley side of the Ranch are used extensively by fall migrants heading south to their wintering grounds. Large kettles of Swainson’s hawks, white pelicans, snow and white-fronted geese, waterfowl, swifts, swallows, and various songbirds ride wind currents up these canyons and over the Tehachapis. In the spring, large numbers of songbirds and shorebirds have been observed dropping into the canyons and waterholes on the Antelope Valley side of the Ranch – some of the first water and cover available after traversing the Mojave Desert. Thus, the conserved lands on Tejon Ranch provide an important and unobstructed route for migratory species that are increasingly threatened with land use changes that are degrading their migratory corridors. More completely documenting the role and function of the conserved lands to migratory wildlife is a top priority for the Conservancy.
Benefits of the Tejon Ranch Conservation and Land Use Agreement
On June 17, 2008 the Tejon Ranch Conservation and Land Use Agreement (Ranch-wide Agreement) was executed by the Tejon Ranch Company and California Audubon, Endangered Habitats League, Natural Resources Defense Council, Sierra Club, and Planning and Conservation League, collectively referred to as the Resource Organizations. The Ranch-wide Agreement committed the Tejon Ranch Company to permanently protect at least 178,000 acres and to provide the Resource Organizations options to purchase conservation easements (or potentially fee title) over an additional 62,000 acres of the Ranch (within five “Acquisition Areas”) at a fair market price determined by an appraisal conducted by the State of California.
In exchange for these and other conservation commitments made by the Tejon Ranch Company, the Resource Organizations agreed not to oppose developments planned by the Tejon Ranch Company within the remaining 30,000 acres of the Ranch. These development plans will still require complete regulatory review and environmental permitting by local, state, and federal governments.
The Ranch-wide Agreement established the Tejon Ranch Conservancy to serve as the steward of the conserved lands, provider of public access to the Ranch, and hub of scientific investigation. The Conservancy is governed by a Board of Directors balanced between Tejon Ranch Company, the environmental group signatories to the Ranch-wide Agreement, and jointly appointed independent representatives. The Board works to achieve the Conservancy’s mission to preserve, restore and enhance the native biodiversity and ecosystem values of the Tejon Ranch and Tehachapi Range for the benefit of California’s future generations. Funding for the Conservancy’s stewardship will be derived from transfer fees on the sale and resale of residential developments on the Ranch.
Much of the 240,000 acres, particularly the 62,000 acres within the Acquisition Areas, is highly developable. For example, the 62,000 acres within the Acquisition Areas is largely relatively flat terrain at the lower elevations around the periphery of the Ranch, and was considered to be the future development areas by the Tejon Ranch Company. Purchase of conservation easements on the Acquisition Areas would eliminate the future land use battles over these lands. In addition, the Tejon Ranch is comprised of over 1,000 legal parcels, which could have been sold to various owners with development plans of their own. Many relatively flat valleys and ridges exist in the interior of the Ranch, which could easily support ranchette style development along with the fragmentation and edge effects associated with this type of development. The Ranch-wide Agreement eliminates forever the threat of development in these areas of the Ranch.
Furthermore, the Ranch-wide Agreement also restricts many potential land use practices that could significantly damage natural resources on the Ranch. Commercial timber harvesting, commercial power plants, commercial feedlots, and recreational off-highway vehicle use are prohibited by the Ranch-wide Agreement. The Ranch-wide Agreement covers 10,500 acres of land potentially available for mining and 7,500 acres of land under consideration for agricultural conversion, eliminating such uses in these locations, but allowing defined mining and farming in designated areas. The Agreement also makes the ranching and hunting operations subject to a Ranch-wide Management Plan that will be prepared by the Conservancy. Following the 5-year Initial Period, the Ranch-wide Management Plan will include management actions that result in enhancement of conservation values rather than merely maintaining them.
