Gray Fox Report: May 2020

Gray Fox Report: May 2020

Disease and the Gray Fox

Submitted by William C. Leikam
President, CEO & Co-founder
Urban Wildlife Research Project
A 501 C (3) Nonprofit Corporation

For the past few months nothing novel, nothing out of the routine has happened over in Foxland. The one exception is that the gray fox pair have changed their pattern of behavior. They have changed the trails they once took on a nightly basis for months. I’d wager that they’ve gone to a new hunting ground, likely out into the big floodplain. The place where they nap during the course of the day remains unchanged. This is typical gray fox behavior.

Since there’s nothing newsworthy to report this month, I have decided to fall back on the kinds of articles that I wrote before Big Eyes and her mate Laimos arrived along the creek. For those who are new to this report, I told stories of the foxes and in January through March of 2017 I wrote about the big die-out at the Palo Alto Baylands Nature Preserve where 25 gray fox succumbed to canine distemper. Now four years later and four years of moving the Urban Wildlife Research Project (UWRP) onto a strong sustainable path going forward, let’s take a look back at canine distemper, the die-out and its effect upon the UWRP.

Prior to Tuesday, January 03, 2017 4:22 PM, canine distemper was not a part of my lexicon. Once we received the final necropsy report from the lead veterinarian for the California Department of Fish and Wildlife, her report stated that the die-out was due to canine distemper with a few other viruses like toxoplasmosis tossed in as well. That woke me up. That and a few other bits of information told me that the ocular (eye) drainage that we had seen over the course of a couple of years; a puss-like drainage from the corner of the eyes, was due to distemper.

That led me back into my photo archives of these foxes, back as far as 2012. I found several pictures of Mama Bold when she was but a year old and not yet teamed up with Gray, showing that drainage in the corner of her left eye. It dawned on me that her immune system was strong enough to hold that virus in check until it simply overwhelmed her some five years later. The last time I saw her alive was on June 18, 2016, five months before the other foxes died.

Knowing then about distemper, I checked the early photo archives of the gray fox population along the creek and there were no overt signs of canine distemper. When they began showing signs, I was baffled for remember at that time, I knew nothing about distemper. How could this eye infection jump from the water treatment plant foxes to the Matadero gathering of gray foxes about a mile away? Using what I thought I knew, I suggested that the eye problem was, like the foxes from the water treatment plant, an injury that had become infected. It was not until we had the report in hand from the CDFW that what I’d seen was a large gray fox population doing battle with distemper. Both enclaves of foxes most likely knew one another and Gray or Mama Bold passed the distemper on to the foxes along the creek.

I sent out through our network what had happened and wanted to know from others who had gray foxes in their area whether they had, had a die-out. Only one came back positive: The Youth Science Institute in Alum Rock, California. They had, had a die-out two years before and their biologist said that their die-out was linked to overpopulation. From there my assumptions were that since the canine distemper had attacked the gray fox population that we had been studying, it too was due to overpopulation. There were just far too many gray foxes in a very small area. I added inbreeding, which depresses the immune system, into the cause as well for I had filmed inbreeding taking place directly before my live camera one year prior to the die-out.

Next month will be a continuation of this issue showing how we began to develop the Collaring Project unless something more dramatic happens like the visual sighting of gray fox pups.

Gray Foxes General Health

This pair is young, most likely first-year dispersals. They appear to be vibrant and healthy. I’ve noticed that this pair do not have intestinal worms like many foxes living along the bay. One can tell if a fox has worms because their scat contains the worm’s eggs; a white rice like sized item in their scat.

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

As of May 2020, we have two adult gray foxes living in the Palo Alto Baylands Nature Preserve.

Section II

Update for the Urban Wildlife Research Project

We need your generous donation be it one dollar or 5,000 dollars so that we can begin the collaring project.

There is a fundraiser for the UWRP on Facebook at the moment. See and please contribute. And while you’re there, check out our Facebook page.

Or you can donate through PayPal on our website ( Urban Wildlife Research Project), check out the short video and go to the donate button on the left of the page. Your donation is tax deductible. The collaring project needs $35,000 and here’s the reason why donate to uwrp?

Here’s a new article that quotes me about aspects of the gray fox. It’s called “Good Neighbor,” by Nancy Baron in Nature-Hood a column in the Coastal View out of Carpinteria, California. I am scheduled to give a presentation at Safari West in July. So far that event has not been cancelled. I will keep the readers of this report updated as things change.

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 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 November and December of 2016, there have been no resident gray foxes 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.

Until next month, I hope that your endeavors provoke thought, are productive, and are rewarding. Take care.

Bill Leikam – The Fox Guy
CEO & President,
Urban Wildlife Research Project
A Nonprofit 501 C3