Room to Move: Why Wildlife Linkages Matter

Juvenile mountain lion climbing a fence. Photo credit: Pathways for Wildlife

Habitat connectivity is about understanding the lives and needs of all the species in our region and giving them what they require to survive. One of those things is the ability to move from one habitat range to another. That’s why we focus some of our strongest advocacy efforts on the wildlife linkages that are the key to protecting the plants and animals that make the Bay Area a biodiversity hotspot.

There are only a few of these critical wildlife linkages left — and they’re increasingly at risk from development. The Santa Cruz Mountains form the green spine of the Peninsula, an oasis of natural habitat running through San Mateo and Santa Clara Counties. These hills are home to redwood and oak forests, grasslands and chaparral, creeks, and streams. But the Santa Cruz Mountains are also a fragmented landscape – meaning that even though there are large blocks of protected habitat, these blocks are often separated by roads, patches of development, and other barriers to wildlife movement. Furthermore, this area is at risk of becoming cut off from other large habitat areas in California. If that happens, inbreeding and inability to disperse to find food and mates could spell disaster for many wildlife populations, with cascading effects on the entire local ecosystem. Climate change, bringing changes in habitat, increased fire risk, and water scarcity, makes it even more imperative to allow species to move out of their usual ranges.

Experts agree that the only remaining linkages between the Santa Cruz Mountains and the rest of the state are through Coyote Valley (just south of San Jose) and Juristac (southwest of Gilroy). In every other location, wildlife movement is effectively blocked by the urban development of Silicon Valley. This is one reason why these two landscapes are the focus of major advocacy campaigns at Green Foothills: they are lifelines for animals in the Santa Cruz Mountains.

Juristac – Protecting the Southern Gateway

At the southern end of the Santa Cruz Mountain range lies a landscape with an incredible variety of habitats and geological features, from rolling hills to nearly pristine sycamore riparian woodlands to rare natural tar seeps. This is Juristac, the sacred heart of the ancestral territory of the Amah Mutsun Tribal Band. For thousands of years, the Mutsun lived and held sacred ceremonies here, in the hills above the confluence of the San Benito and Pajaro Rivers.

Although Juristac provides habitat for many at-risk species, including mountain lion, American badger, California red-legged frog, California tiger salamander, and golden eagle, the critical significance of Juristac for habitat connectivity lies in its location. The Santa Cruz Mountains come to an end at Juristac, and in order for species here to travel across the Pajaro River valley to the Diablo Range to the east, or across the Chittenden Gap to the Gabilan Range to the south, they must pass through Juristac. [See map]

But Juristac is threatened by a proposed sand and gravel mine that would severely impact these linkages. The Sargent Ranch Quarry would excavate four pits hundreds of feet deep in the hillsides of Juristac, literally scooping out these hills and leaving behind giant cavities. These pits, together with the new roads for heavy machinery, a conveyor belt more than a mile long to move the sand and gravel, and a waste processing plant the size of 10 football fields, would form a major barrier to wildlife movement. Aside from the physical destruction of the landscape, the noise and activity involved in an open-pit mining operation would deter many animals from venturing near the site. Further, the mining pits and roads connecting them would lie directly across a critical undercrossing for Highway 101.

Wildlife in Juristac. Photo credit:Amah Mutsun Tribal Band

Green Foothills is partnering with the Amah Mutsun Tribal Band in their effort to protect Juristac as a wildlife linkage and sacred place. Santa Clara County has been working on a draft Environmental Impact Report (EIR) for the Sargent Ranch mine for several years. The County has continually delayed its release, but the most recent information from the County is that the draft EIR is expected this June. In the meantime, Green Foothills, the Amah Mutsun Tribal Band, and our partners are working to keep this important issue in the public eye.


Coyote Valley is the other critical wildlife linkage connecting the Santa Cruz Mountains to the Diablo Range. This is one reason our recent victories in Coyote Valley are so important – it is now safe from urban-scale development.

However, the threat to Coyote Valley is not over. Three landowners, who want to build two huge Amazon-style warehouses on the site of the Spina Farms farmstand, have filed a lawsuit challenging the City of San Jose’s rezoning of North Coyote Valley. Also, the City will soon be conducting a study for potential increased commercial and recreational uses along Monterey Road, which is already a roadkill hotspot.

Wildlife tracking studies have repeatedly found numerous animals—mountain lions, coyotes, bobcats, deer, badgers, gray foxes, and others—in and around the valley floor. Animals have also been documented crossing the two major barriers of Highway 101 and Monterey Road via culverts and underpasses. But these animals must run a gauntlet of dangers. Monterey Road in particular is a serious barrier, with only one somewhat functional undercrossing – a culvert that can be blocked by debris or high water. Nighttime lights, noise, and human activity also hamper wildlife passage and habitat in much of Coyote Valley. As a result, although Coyote Valley functions as a wildlife linkage, it is a highly impacted one and forms a very tenuous lifeline for the animals that utilize it.

Green Foothills is monitoring the Monterey Road study to ensure that any expansion of commercial or recreational use there does not increase wildlife mortality on Monterey Road.

Coyote Valley. Photo credit: Treasa Hovorka


Protecting open space is about more than just preventing development on parcels of land—it means meeting all the needs of the diverse species in our region, including the room to move. When we protect, enhance, and restore our local wildlife linkages, we’re working to safeguard the biodiversity and richness of the Bay Area ecosystem and making this a place where wildlife truly thrives and communities live in balance and reciprocity with nature.

An earlier version of this blog post appeared as an article in the Summer 2021 issue of greenfootnotes, Green Foothills’ printed newsletter.

Leave a Reply

Your email address will not be published.


You are leaving the Green Foothills website to go to our Protect Coyote Valley website.

Continue on to PCV Petition