Urban Wildlife Research Project

The mission of the Urban Wildlife Research Project is to document gray fox behavior in the Palo Alto Baylands region in order to establish healthy habitats and develop the biodiverse wildlife corridors necessary for their survival. As a result, UWRP helps San Francisco Bay area people and wild nature coexist through research, advocacy and public education.

Watch this short video, and then consider donating to our Corridor Project, designed to create a healthy environment for all wildlife.

Gray Fox Report for October 2021

What’s Going on In the Mind of A Gray Fox?Part II

Last month in Part One of this report, we ended with listing the gray fox’s tools of perception, in other words its five senses: Hearing = 45%, Smell = 40%, Sight = 9%, Touch = 4%, Taste = 2%. According to Stefan Pociask who worked at Arizona Game & Fish Department “[It’s] their keen hearing. That’s their superpower.” He adds, “They can pin-point the barest rustling, the tiniest squeak or scrape beneath a foot of snow, and crash through that blanket of snow to locate their prey, within an inch or less of accuracy.” Remember, that none of this is founded in science as such but is to be considered speculative; trying to uncover what’s happening in the mind of a gray fox. Read More….

SF Bay Area Wildlife Corridor

Our vision is a San Francisco Bay Area Wildlife Corridor. UWRP notes that as population, development, and sea level increases, it is of utmost importance that the wildlife thoroughfares are identified and preserved. To help maintain California’s natural genetic diversity, UWRP’s goal is to map, protect, and enhance the corridors that wildlife use to travel from one region to another. We will partner with other wildlife organizations and government agencies to research and link the wildlife corridors to create a San Francisco Bay Area Wildlife Corridor to ensure the protection of the region’s rich natural heritage.

SF Bay Area Wildlife Corridor

Beginning with the South Bay

After years of researching the behavior of Gray Foxes in Palo Alto, some observations have left us doubting the genetic health of the foxes; including floppy ears, incest, and overpopulation. We began to hypothesize what factors led to these conditions. Could it be that human development has isolated the foxes, preventing them from leaving the baylands? UWRP set out to answer this question by broadening their search of the gray fox to near by San Frasiquito Creek and the surrounding baylands. To our surprise, most places we looked, we found signs of these ashy canines.

One of our research subjects, a Gray Fox named Cute, lives at the Palo Alto Baylands.

We began mapping our sightings and widening our search to all of Silicon Valley and the mountains surrounding. Anyone can contribute to our project by sending us their Gray Fox sightings and photos. The Gray fox has been found on the Campuses of Google, Facebook, and Stanford. As well as in Downtown San Jose, at the Sharks Stadium and running down 15th street through the Naglee Park neighborhood. These foxes, we’ve dubbed Urban Gray Foxes, are showing signs of adaptation to the urban landscape, following the footsteps of the raccoon, skunk, and opossum.

Silicon Valley Gray Fox Corridors

After creating the fox map we came up with a new question, how are these different populations of foxes related to one another? To answer that we’ve designed a DNA project that will commence late 2016. We will revisit the locations on our fox sightings map and collect fresh scat for analysis by a university lab. We hope to be able to find evidence of genetic linkage between the Gray Foxes in the Santa Cruz and Diablo mountains to the foxes living around the bay. From this data we can hope to discover which creeks are a viable corridor or path from mountains to bay. We will also do a complete DNA marker analysis on the scat to better understand the Gray Fox’s diet in the many different kinds of habitat around Silicon Valley.

A family of Gray Foxes, on of the creatures affected by habitat fragmentation.

When looking at the fox sightings map, UWRP connected the dots to find the corridors, or paths the animals take to navigate the urban landscape. They have identified Coyote Creek, Guadalupe River, Los Gatos Creek, and San Francisquito Creek as possible paths from the in the mountains to the bay. When looking at the map you see the big picture, but out in the field when searching for the exact path the animals take, we find their route can be complex and dangerous. Through backyards, under culverts, over barbed wire, and across busy freeways. We hope by identifying these problem areas we can make the path safer for wildlife and humans; by correcting fencing to channel wildlife under culverts and constructing or improving wildlife crossings.

Road Kill Hot Spots occur in areas where wildlife frequently crosses the road, usually along a wildlife corridor. This photo is of a bobcat, hit on Hwy 17 while attempting to follow Trout Creek. 

Habitat loss, fragmentation, and isolation are major factors in the decline of our wildlife populations worldwide. Citizens and organizations can help this project by volunteering, donating funds for research, and becoming a member of the SF Bay Area Corridor Coalition. Fill out a form on our contact page to learn more.

Coyote Creek and Coyote Valley

Coyote Creek flows north from San Antonio Valley, connecting with many creeks along the way through San Jose and out to the Bay. One crucial connection point for wildlife along this creek, is a place known as Coyote Valley. This area is the closest distance between Silicon Valley’s two mountain ranges, The Diablo(or Hamilton) and Santa Cruz Ranges. Coyote Valley is just 0.4 miles at the narrowest end and 2 miles at the widest, with Highway 101 bisecting the land. The valley’s land use is mostly agricultural and contains some of San Jose’s last agricultural land from the days of The Valley of the Heart’s Delight.

This route is how the valley’s wildlife connects with the rest of California and the continent. Without this linkage our wildlife may be stuck in the Santa Cruz Mountains, with little place to go. Isolation can lead to poor genetic health, disease, population decline, and even extirpation(or local extinction) of certain species.

Coyote Valley at Bailey, veiw from Metcalf Canyon on the Diablo Mountians side, looking towards the Santa Cruz Mountains. Hwy 101 intersects the wildlife corridor, posing a risk to wildlife and drivers.

Wildlife researchers at De Anza College and Pathways for Wildlife have done some amazing research tracking wildlife across Hwy 101 and the valley floor. They found that some wildlife uses about 30 crossing structures to find safe ways of crossing the Valley and freeway; such as underpasses, overpasses, culverts and waterways. There are talks of a Wildlife Crossing over Hwy 101 to provide a car free path for wildlife through Coyote Valley. Below is some preliminary research UWRP has done in the area north of Coyote valley which still provides linkage between mountain ranges.

In the map above, Coyote Creek flows under the Hwy 101 and 85 interchange. UWRP followed the foot prints of animals from the Diablo Mountains, safely under 101 and 85 and on to the Santa Cruz Mountains side. We documented the tracks of Bobcats, Coyote, Gray Fox, Deer, Boar, Rabbits, Ground Squirrels, Harvest Mice, Quail, lizards, and frogs passing safely under the freeway. Even spiders, butterflies, and newts need these corridors as a safe link around our man made obstacles. Despite the underpass, wildlife still gets hit along the motorway in this location, due to inadequate fencing. Our goal is to partner with Caltrans and land owners to improve fencing to minimize animal vs automobile incidents and direct wildlife to safe passage.

Coyote Valley is under constant threat of development. Open flat land is hard to come by in San Jose and fetches a pretty penny. Coyote Valley could very well end up another piece of the concrete web of Silicon Valley tech campuses and industry, but, there is a major effort to preserve the land. Join the effort to preserve Coyote Valley, find out more at: https://www.facebook.com/ILoveCoyoteValley/

Coyote Valley, a bridge between mountain ranges.

The Guadalupe River Corridor-The Santa Cruz Mountains to the San Francisco Bay

From the mountain springs of Mt. Humunhum and Loma Prieta, through Downtown San Jose, and out to the San Francisco Bay; the Guadalupe River may be the most intact creek corridor in the region. But for larger animals like the bobcat and mountain lion it may be too over developed to allow passage from mountains to bay. Downtown sky scrappers are built, sometimes with little or no buffer to the bank of the river. The sandy, rocky river bottom is replaced with concrete blocks to prevent erosion and speed up the water’s journey to the bay to prevent flooding. These areas with poor habitat conditions and little to no plant cover provide little opportunity for wildlife movement. Yet the Coyote and both Red and Gray Foxes have been spotted in the Guadalupe River Park and Gardens in the middle of Downtown San Jose.

Concrete River bottom Coleman Ave. Downtown San Jose.

Riparian Setback; The natural vegetated space between a stream or body of water and human development. Many local governments in the nation have mandated Riparian Setbacks, for example, Contra Costa County does not allow building within 150 feet from a stream. Very few cities and developments along the creeks and rivers of Silicon Valley take Riparian Corridors into consideration. With out proper setbacks our bayside terrestrial and aquatic wildlife may be left cut off from the rest of the state.

Fish Need Corridors Too

15 inch endangered Steelhead Trout from Guadalupe River Downtown San Jose.

Our anadromous, endangered listed, fishy friends like the Chinook Salmon, Steelhead Trout, and Pacific Lamprey use these creek corridors as well. Improper Riparian Setbacks and concrete river banks, among other things, negatively impacts them too. These fish need cool uninterrupted flows with a proper river bottom. Their journey through the Guadalupe River often stops before the finned ones reach the cool mountain streams; at the dams: Calero, Almaden, Guadalupe, and Vasona. The dams not only cut off the flow of fish upstream to better spawning grounds, they stop cobble stones from rolling down stream to create good fish spawning habitat. Our lower watersheds eventually become bogged with mud and silt. The concrete river bottoms in the more urban reaches of the streams are troubled with unnatural and high temperatures. Proper Riparian Setbacks, good cobble, and improving fishes access to mountain streams are what the declining fish populations are signaling for.

Trial Camera Footage

Wildlife Behavior Analysis | Gray Fox Playfulness and “Hugging” Behaviors

Bay Area Wildlife Habitats Are Disappearing. Fox Guy Has A Plan.

Wildlife Behavior Analysis | Red Fox Sightings


The Gray Fox Die-Off of 2016

Wildlife Behavior Analysis | Gray Fox ‘Laimos’ Shows Off

More Trial Camera Footage

Bill Leikam “The Fox Guy” | A Year With The Urban Gray Fox [2017]

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What We Do

SF Bay Area Wildlife Corridor
Our vision is a San Francisco Bay Area Wildlife Corridor. UWRP notes that as population, development, and sea level increases, read more…..

Gray Foxes of Silicon Valley
UWRP’s Bill Leikam and Greg Kerekez track Gray Fox families through the marshes of the South San Francisco Bay, along the urban   read more…..

The Urban Wildlife Research Project of Silicon Valley will complete an in-depth study of the effects that Urbanization has on the critical regions read more…..

Burrowing Owls of the South Bay
In the Santa Clara Valley there are many signs that our ecosystems are in danger. One major indicator is a species of bird that is vanishing from our basin at an alarming rate.  read more…..

Beavers in Downtown San Jose, CA
After over 150 years of extirpation in Santa Clara Valley, a family of California Golden Beavers have inhabited a stretch of the Guadalupe River in Downtown San Jose, California.  read more…..

Herbicides: Impacts and Alternatives
Our exploration of Santa Clara County’s city streets, and open spaces have led us to discover some environmentally unfriendly practices being conducted by residents, cities, and government entities in our area.  read more…..

Feeding the Feral: A Study on Feral Cat’s Environmental Impact
Feral Cats on the prowl, an all to frequent sight while documenting urban wildlife. Some cast aside by their human owners, others born wild on the city streets, creeks, and open spaces.  read more…..

Palo Alto’s Anaerobic Digester Plant to Displace Gray Foxes
The wildlife in the gray fox research study area at the bay lands is in danger. The City of Palo Alto is delaying the capping of the landfill and the expansion/restoration of Byxbee Park so that it can assess the feasibility of installing an anaerobic digester.  read more…..

Rodenticide: Impacts and Alternatives
The food chain is sacred, continual, and encompassing. Rodenticides are a major threat to food chains around the world. read more…..

Presentations-Guided Hikes-Out Reach
Urban Wildlife Research Project has made education a focus of their mission. Their goal is to share the knowledge they’ve gained about the wild, to instill a greater sense of responsibility in the current and upcoming generations, so the wildlife diversity of Silicon Valley may persist with time.   read more…..