Gray Fox Repopulation?

by William C. Leikam
President, CEO & Co-founder, Urban Wildlife Research Project

Prior to October 2018, the last gray fox to pass through the baylands after the massive die-out of 2016 occurred at Trail Camera #9 – 02 – 04 & 05 – 2018 – Fox Hollow Gate – IMG-0013 – Tagged: Gray fox trotting back toward junction – See camera @ 12:06 AM. From then on, the eight trail cameras posted at the baylands recorded a red fox, the usual raccoons, opossums, and skunks. Additionally, there was an explosion of woodrats, jack rabbits, an ever-increasing number of field mice, lizards, gopher snakes, gophers, voles, both ground and tree squirrels and all other manner of critters that the keystone predator, the gray fox, had once fed upon. When the foxes lived there, they kept the environment at the baylands in systemic balance.

As the months pressed on, I sat here nearly every morning watching and tagging a multitude of 30-second video files of mostly the same critters day after day, wondering whether, on the next click, the next file would show a gray fox trotting through near Fox Hollow Gate. Right there, on that road passing the gate, all wildlife that either migrates or at certain times of the year disperses, between Pacific Shores in Redwood City and south around Sunnyvale, were naturally channeled through Fox Hollow. The geography of the riparian habitat dictated that the gray fox and other wildlife would travel there.

Knowing the cycles of the gray foxes, my expectations varied from month to month. For instance, in early May the pups are busy nursing and sleeping but by the end of the month, they are out exploring. July and into August these young foxes are romping and wrestling and dancing through life with siblings and with their parents. By mid-November and into December, the pups are ready to leave home to find an unclaimed territory and a mate. That’s what I had been waiting for.

At the same moment, there are gray foxes that are seemingly vagabonds. They are usually males but once-in-awhile a female will show up. They live freely and move from one region to the next during the course of a year. They never settle down. When they traveled through Fox Hollow, as they passed by those three trail cameras stationed at the gate, one or more of the cameras caught their image trotting through but they never stayed.

Early morning, dark, October twenty-second, 2018 on my computer screen at 5:37 a dark, grainy animal trotted through Fox Hollow. I stopped the video. I thought, “That looks like the trot of a gray fox.” It just moved with that certain, smooth rhythm. It trotted across the road, over by the Alkaline Salt Bush, and rapidly dissolved into the darkness. Grainy video; hard to really be sure I saw it right. I played it again, stopped it, looked, started it again looking for the tell-tale signs that it was either a gray fox or just one of the big feral cats that live in the region. Hesitantly, I tagged the video as a gray fox.

The following morning, October 23rd as I reviewed file after file, clicking on the next one, seeing an opossum cross the road, a raccoon with one eye followed by her juvenile cub and then I hit on file number eight and there it was: Urocyon cinereoargenteus the gray fox. Clear. There. I cried, “Yes, yes, yes, there it is!” It trotted toward the junction. I tagged it and set one copy aside.  I continued tagging the files. And then bingo at 8:36 PM another gray fox filled the video screen headed for the junction too, but it stopped and checked something off to its right. Finally, at 11:36 PM a gray fox passed back through coming from the junction to the gate traveling in the opposite direction from the other two sightings. It was impossible to tell whether or not this was a single gray fox, a couple of them, or three. Whatever the case, the issue becomes, “Will it remain in the region?” Only time and patience will tell.

So, if this signifies the return/repopulation of the gray fox to the baylands, I need to somehow measure their impact as they return the balance to the environment at the baylands. We not only need to see that in the short term, but we need to look at that in the long term too. When I talk with people about the foxes, they invariably want to know if the foxes have returned. I shrug and say, “I don’t know. We need to know more before we can conclude much of anything.”

Gray Foxes General Health

To date, gray fox has been seen in the Palo Alto baylands to date 23 October 2018.

Total Numbers Of Gray Foxes in the Palo Alto Baylands Nature Preserve

Unknown.

Section II

Update for the Urban Wildlife Research Project

About a week ago, maybe a bit more now, I was interviewed on the trail while taking care of my trail cameras when Sheri Baer and I met at the end of Embarcadero Way and headed on out to set up my eight trail cams. She has written a feature article about what I do out there at the baylands. It will be available in their December edition. Check out Punch Magazine.

To find out more about us, search Urban Wildlife Research Project, UWRP, gray foxes, wildlife connection, linkages, corridors and several documentaries and clips on YouTube    

  1. Check out our Facebook page.
  2. If you haven’t had a chance to read at least some of the articles that have been written about our study of gray fox behavior and our corridor work, click on these links as they will take you to the source: Bill Leikam – The Fox Guy, and Greg Kerekes & URWP

Section III

Gray Fox, Baylands Goals

Within the permit that allows the Urban Wildlife Research Project to conduct its study of the behavior of the gray fox at the Palo Alto Baylands Nature Preserve, the objectives covered area:

  • Monitoring of urban gray fox Denning sites in Palo Alto Baylands.

This is being accomplished during the period when the gray foxes use a den site. It is one of the prime locations for gathering most of the behavioral data of the litter and for adults alike.

  • Assessment of status and population trends of Baylands urban gray foxes

Since January 2019 a pair of resident gray foxes have claimed territory at the Palo Alto Baylands Nature Preserve.

  • Identification of habitat features that promote the presence of urban gray foxes

After considering this and talking with people who know how to restore habitats, we need to assess what kinds of plants, including the Alkaline Salt Bush, would grow best along the edge of the saltwater channel and alongside the marsh. We need to grow a permanent habitat that contains the corridors and plant it as soon as possible. We’ll keep an eye on this as this is a critical link between the southern region of the Baylands and the northern region.

  • Assessment of reproductive success and identification of factors that promote successful reproduction

Open up the pinch-point along Matadero Creek by developing thickets that link one area to another, instead of the present “islands”.

  • Identification and assessment of possible dispersal travel routes.

Presently there can only be guesses as to dispersal travel routes. We intend to make this important question much more concrete when we attain our collaring/take/capture permit from the Department of Fish & Wildlife.