6,000 Acres of Prime Open Space in Los Angeles County Now Protected

The largest undeveloped private property in L.A. County is now part of a protected ecological area that will preserve habitat and expand wildlife corridors between the San Gabriel, Sierra Madre, and Santa Susanna mountains.

2 minute read

July 11, 2022, 7:00 AM PDT

By Clement Lau


Santa Monica mountains

MRCA /

With the acquisition of 6,000 acres of open space, California is a step closer in its effort to conserve 30 percent of the state’s land and coastal waters by 2030, also referred to as the 30×30 initiative. The largest undeveloped private property in Los Angeles County is now part of a protected ecological area that will preserve habitat and expand wildlife corridors between the San Gabriel, Sierra Madre, and Santa Susanna mountains. 

The 6,006-acre Hathaway/Temescal Ranch property is 40 miles northwest of downtown Los Angeles and adjacent to both the Angeles National Forest and the Los Padres National Forest between Castaic Reservoir and Lake Piru.  Hathaway/Temescal Ranch is land that has been used for ranching and grazing, but other than a modest ranch home, it is undeveloped. The property includes wetlands, rolling hills and is within the flight path for condors from the nearby Sespe Condor Sanctuary.

The property was acquired in three phases by the nonprofit Trust for Public Land, and transferred to the Mountains Recreation and Conservation Authority, a local government agency exercising joint powers of the Santa Monica Mountains Conservancy, and the Conejo and Rancho Simi Recreation and Park Districts. The California Wildlife Conservation Board was key to acquiring the land and funded nearly half of the purchase, including $3.5 million to secure the final phase.

The property sits within a Los Angeles County-designated “Significant Ecological Area.” It helps create critical east to west linkage between the San Gabriel and Sierra Madre mountains as well as a north to south linkage between the Sierra Madre and Santa Susanna mountains, both highlighted in the South Coast Missing Linkages Project, which is a comprehensive plan for a regional network that would maintain and restore critical habitat linkages between existing reserves. These linkages form the backbone of a conservation strategy for Southern California.

The acquisition is another step forward toward California’s 30×30 conservation goals. This commitment is part of an international movement to protect nature across the planet. A few months ago, the California Natural Resources Agency released Pathways to 30×30: Accelerating Conservation of California’s Nature, responding to Governor Gavin Newsom’s nature-based solutions executive order, which identified California’s lands as a critical yet underutilized sector in the fight against climate change.

Thursday, July 7, 2022 in Pasadena Star News

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