UWRP Newsletter: Gray Fox Report for March 2015

Welcome to the Urban Wildlife
Research Project Newsletter

Gray Fox Report for March 2015

by Bill Leikam, The Fox Guy

Gray Fox Report for March 2015

Respectfully Submitted by William C. Leikam
Founder of the Urban Wildlife Research Project (UWRP)

Date Submitted: Wednesday, April 1, 2015

It’s the waiting time; that time when many of the females are staying close to their natal dens. There are exceptions, however. From all indications, short of actually seeing them, Mama Bold has given birth to her litter in the old natal den (continuously in use for 24 years) where she and so many other gray foxes in the local area have been born. Dark Eyes, has been absent for the past two weeks. That suggests that she is either denned up or she too has had her litter. (I do not trespass into the actual natal den and that’s why I do not know for certain if the pups have been born.) Little One’s sides still bulge with pups yet to come. Then there’s the adult female Cute who, last year had a single pup. I’m not sure whether she is pregnant or not.

Lately, over the past two weeks or so, she’s behaving very differently from her usual self. Before the onset of this “new” behavior, she’d trot along at a quick pace, sit and scratch, and groom; all the usual things that gray foxes do but lately she appears to be “spaced out” as though her mind and attention is elsewhere. She slowly walks along the edge of the grass, sometimes reaching up to pluck away a stalk of wild wheat. She seems to be in her own world and I suppose that could be due to changes due to pregnancy manifesting in this changed behavior. If Little One and Cute are pregnant, they should be giving birth within the next two to three weeks as April tends to be the birthing month for these gray foxes.

With the coming of new litters, the gray foxes have already “staked” out their territory but what does one do when there are two dens virtually side by side? The two males Blue and Dark have been struggling for that territory. It’s obvious that neither likes the presence of the other. For instance, one day when Blue lay at the edge of the grass next to the brush, Dark saw him. The two males bristled, arched their tails – an indicator that tells all in the vicinity to beware – and in the flick of an eye, Dark shot off after Blue. They crashed through the brush, and in their flight I heard the breaking of dead branches as they tore beneath the canopy. Within 10 minutes after that chase, Blue sat at the edge of the grass and the brush-line looking for Dark.

Upon examining and tagging my trail camera video files, on 3/17/2015 the gray fox Blue casually walked out into the big clearing, when suddenly he dashed off, came around and flew past the camera with another fox in immediate pursuit. At that time, it was just two foxes chasing. It wasn’t until that afternoon when I saw the gray fox male Dark limping along the trail that I realized what had happened. Putting two and two together, it was obvious that Blue and Dark had fought the night before and that Dark’s knee had been nipped. It wasn’t a serious bite in that four days later, Dark no longer limped.

It’s hard to tell what’s going to be resolved, if anything, because both males “claim” the territory. It appears as though Blue and Dark Eyes have teamed up and will have pups. Last year she had four but I never saw her mate, or at least I don’t think I did. Even to date I’ve not seen Blue and Dark Eyes together grooming each other as do Dark and Cute, but then again each pair have their own, individual ways of responding to each other. Last year they had a single pup that I came to call Midget and during the months as their pups developed, all of the pups and the adults got along reasonably well although on occasion the pups got into fights. In one of those fights with another pup Tippy of Dark eyes litter, Midget had a laceration above and below his left eye. It festered but eventually healed.


As previously noted in the February fox report, there are four adults in the area that had pups and reared them during the 2014 season. Two of them, Papa Gray the male and Mama Bold the female, have maintained and secured their territory. The other adult foxes that I have been monitoring are the aforementioned adult female Cute her mate Dark, and then in another location there is Little One, that had no litter last year but looks to be pregnant this year. She has paired up with a newcomer to the area, Brownie. The other pair are Blue the male and Dark Eyes the female. There is one female adult, Helper, that had no pups this past season nor over the two previous seasons. It appears as though she will not have a litter this season as well. I am beginning to think that she is a barren/infertile female gray fox. Total adult population that I have been monitoring for the past four years equals nine adults including Helper.

As for the number of juveniles still in the area there are three: Tippy and Pale. These two pups never dispersed.

This gives a total of both adult and pups remaining at the baylands to eleven gray foxes. In July 2014, there were 26 pups and adults combined.


As an update on events occurring with the UWRP:

This year we expect to be funded by the National Wildlife Federation (NWF). Amount is unknown at the moment.
  1. We are working to develop an integrated, seamless animal corridor from Redwood City, south along the bay into the Alviso area and then north to the southern edge of the Oakland Airport. This work is already underway.
  2. We have been featured as one of the most important urban wildlife projects in Northern California by the NWF and on March 17th we were once again a featured part of the NWF’s annual gathering at the San Francisco Flower and Garden Show.
  3. A feature, front page article is being published about my study of the gray foxes in early April in the Palo Alto Weekly.
  4. A new urban wildlife book will be published this year that features a chapter on our research/ study being done at the baylands on the gray fox.
  5. A new documentary has been released. See it below, or on YouTube.
  6. We are being asked by organizations, corporations, and two universities to advise them on the gray foxes in the area. The most recent one was to advise the managers at the Palo Alto Technology Center on the behavior of the gray fox. They did not know what to do when they went to their cars, only to find a gray fox sleeping on top or on the hood.
  7. Recently we did an assessment of the local gray foxes at the Presidio in San Francisco.
  8. During March we were asked to present our work to two organizations: Docents at Natural Bridges State.
  9. Park in Santa Cruz and to the faculty at the Walden West Science Camp and School.
The Gray Foxes of Silicon Valley
The Gray Foxes of Silicon Valley
Until next month, I hope that your endeavors are productive and rewarding. Take care.


Gray Fox Report for December 2014

The heavy rain and subsequent flooding along Matadero Creek claimed the life of one of the gray fox pups/juveniles. Several of the foxes including the juvenile that drowned, were there in the overflow channel that morning. Just before that first heavy downpour, at 7:00 AM I was at Matadero Creek ready to leave. The creek was much the same as it had been all year long; water and a few Mallards.

At around 9:00 AM as I sat working at my computer, I realized that the rain was coming down heavily. Having grown up on the banks of a volatile creek, I knew how rapidly a creek can fill. Additionally, Matadero Creek, like all of the other creeks in the area are the run-off channels from the streets throughout Palo Alto. That meant even more water coming down Matadero Creek. I decided to go back out to the creek and see what changes may have taken place. I arrived at the Matadero Creek Bridge by 9:15. The water rushed brown with mud having already risen from nearly nothing two hours before. The water had risen at least eight feet. It filled the overflow channel approximately 2.5 feet deep and that meant the creek was full all the way across to the levee on the north side of the creek. There was nowhere for the foxes, the raccoons, the opossums, the wood rats and other wildlife to go.

As flood water subsided in the channel, I went on over onto the levee road along the backside of the Animal Services area. Down along that road I found one of the pups that had made it to high ground. It took several days for the other foxes to return. All were to one degree or another traumatized by the flood. For example, the pup that had found high ground before the flood had been a relaxed, easy going little male but after the flood, he was tense, anxious, hyper-alert at, for instance, a noise, or a bird landing nearby. It took that pup a week to recover. As well, that pup before the flood had a companion. They were together all of the time. The two of them, Tense and Tippy, defied the solitary nature of the gray fox because they traveled together. After the flood, that little pup Tense did not return and I assume that it got caught up in the flood water and was swept away. There may well have been other casualties involving the wild gray foxes, the ones that do not often show up along with the others.

Gradually, one by one, the surviving gray foxes both adults and a single remaining pup belonging to Dark and his mate Cute by the name of Midget showed up. Dark, the adult male was the last survivor to appear one morning back on the overflow channel. As of this writing the foxes that I normally monitor are emotionally back to being themselves. It also appears as though they learned something from that first deluge in that since then we have had a couple of other heavy rains and the foxes are gone for a day or two.

About three weeks ago head of facilities Wilma Vanson at the Palo Alto Technology Center contacted me because foxes had “invaded” the center and were sleeping on cars, walking up to people, begging, etc. People who worked at the varied offices and corporations who I talked with, enjoyed them but management was afraid that a fox might be offered food and it might bite someone and then there’d be a law suit. I gave her a list of actions that needed to happen within the facilities that she controlled. Tightly cover dumpsters, don’t feed any wildlife, even feral cats, etc. In the end there was no way to eliminate the foxes because if one was removed another would slide into the empty slot. The juvenile gray foxes were on the move, dispersing. It took the city of London England 15 or so years to get the message: We need to learn to live side-by-side with our urban wildlife nearby.

As mentioned before, at this time of year there are no territories nor are there dens as we normally think of a den, i.e. a home base anywhere nearby. Those kind of dens only exist for maybe 20 days before the foxes move the den’s location. I have watched dens develop and dens dissolve. Given the latter as solitary animals, the foxes simply walk in circles to make a soft place to bed down in most anywhere they feel like it. For the most part they will remain in the same location for from two to five days before changing their location to sometimes as little as 50 yards away or even up to half a mile distant. But, and this is happening at the moment, the pups, this year’s juveniles, are moving farther and farther from the region where they grew up. Strangers, new comers, are showing up at the baylands.

At the water treatment plant, three of the five pups born to Bold and Gray have gone. Almost daily I see foxes appearing who are strangers to the area. Two of these have hung around, intermingling with and enjoying the company of other juveniles that were born in that region. These are the juveniles who are on the move looking for a suitable mate and suitable territory of which there is very little remaining in the baylands. If a connection doesn’t’ work, the stranger leaves. I have seen this not only now but in years past. The number of foxes at the baylands is in flux. On Friday, December 26, 2014, I came upon a total of 10 foxes and that included the two dispersing foxes, the strangers. These ten foxes were on both the north and south sides of Matadero Creek.

The gray fox population will shake down during the month of February 2015 and by March 2015 it will become once again stable because the pregnant females will understand that a new litter is coming. Their mates, the males, scout the area and mark their territory when he knows that he can find enough food for the pups to grow up on.

Aside from the foxes, Greg Kerekez and I have formed a partnership called the Urban Wildlife Research Project (UWRP). Over this past year we have spoken to various organizations. I have been interviewed twice on radio shows: One in Auburn, Ca. and the second in southern Oregon. Greg and I have made public presentations about the urban wildlife. Across the internet I have been asked for advice regarding the behavior of the gray fox and other mammals as well. UWRP’s work has been referenced in doctoral programs at major universities nationwide; locally at San Jose State University and at U.C. Berkeley. All has been successful. In the coming year, we are being funded by the National Wildlife Federation. Our goal is to knit together all animal corridors between the southern reaches of Redwood City, south along the bay and then north up to southern part of the Oakland International Airport. As a natural fallout from all of this, we are being invited to make presentations on the wildlife that lives at the perimeter of the south San Francisco Bay. Our educational part of the UWRP is already happening.

Feel free to ask any question at all about urban wildlife. Visit us at uwrp.wordpress.com. January’s report will most likely concern itself with which foxes are pairing up and which foxes like Gray and Bold will stay together.

Gray Fox Report of February, 2014

Location: Public access areas along the levee road skirting Matadero Creek. Last report – 12/27/2013

This slideshow requires JavaScript.

(Picture #1: Helper Female  #2, Creek vaulting over a 10 foot channel)

As mentioned in my last report and as a quick reminder I have been hampered in my monitoring of the gray foxes due to having my Palo Alto City’s permit withdrawn. The city required that I attain a Department of Fish & Wildlife Scientific Collection Permit before I could continue my work. A year has passed with no permit in sight. Because of this, I have enlisted Senator Jerry Hill’s staff to try to trace it down. Even they are having difficulties but the last word on this is that the State Department of Fish and Wildlife is trying to find my application.

A little aside here about mating behavior. Normally, in low to medium density environments, gray foxes tend to be monogamous but where there are high density populations monogamy breaks down in many but not all cases. (There are always exceptions to these kinds of generalities.)

 Over this past month, the question of which of the females will den up this year with Creek, has been answered. Creek and Helper have moved out onto the Renzel Wetlands and have denned up near or within the ITT Facility. Now the question becomes what will Little One do since she, as far as I can tell to date, has no mate? Will she take on the role of helper female to Creek and Helper once they have their litter? In other words will the roles be flipped this coming season? Will she find herself a mate out there on the floodplain? I’m tracking that issue now.

 January and February are interesting months because in the environment that I am studying, until very recently there are no territories marked and there won’t be until most of the dispersing foxes from last season’s litter either move through or they find a mate and sufficient range to feed their litter. If we look at this it makes sense: The young, the first year gray foxes, have been moving out to find their own mates and their own territory. Therefore, the animal corridors and byways through the riparian (creek-like) areas are open from about November through January. This allows these dispersing gray foxes free access to territories further afield. Once dispersal has taken place, then territories will be marked and defended. However, if a young gray fox decides to stay in an area for too long, it will be urged along by the dominant gray in the area. Recently, I saw just such an encounter. Creek the alpha male met with another fox that had been around for three days prior. They fought. At one point in that intense fight the two of them were up on their hind legs pounding each other with their paws like boxers. I never saw the intruder after that.

In a nutshell, that’s what’s happening. Please feel free to send me any comments or questions.

 Finally, if you know of an organization that would like to have me come and present my talk “A Year with the Urban Gray Fox” I would much appreciate the referral. My photographer partner in the Urban Wildlife Research Project, Greg Kerekez, also has a presentation on Burrowing Owls and more. Not only do we present to corporations, and organizations, but we will also come to people’s homes to present this. Let me know if you want to invite your friends over for a presentation on the Gray Fox. Just reply to this email.

 Resectfully submitted,

Bill Leikam, aka The Fox Guy

Director: Independent Urban Gray Fox Research Project

January 2013 Monthly Fox Report

Monthly Gray Fox Report

by Bill Leikam

Sunday, January 27, 2013

Bold(female) with Rabbit Bill Leikam ©2013
Bold(female) with Rabbit Bill Leikam ©2013

Over the period of just over a month since my last report, a few changes have taken place with the gray foxes at the baylands. Since early December and on into January, the young foxes, the yearlings, have ignored the usual territorial boundaries as they are looking for their own territory and a mate. Foxes are coming and going through the area. They are for the most part solitary but they will pair up for a week, maybe two weeks and then move on. Along the creek, there are at least two and maybe four foxes both in the floodplain and along the creek down toward the slough. Last month there were none.

The alpha female that I call Bold and who fought her “father” Squat for the natal den in fox hollow left the area for about six weeks. Before leaving, however, one morning I followed her, observing and taking notes as we went. She trotted on down into the hollow and bounded back into the brush, right where the den is located. Within a minute or so, coming up the road through the bare light of dawn trotted a fox hot on her trail, just sniffing everywhere she’d walked. His nosed swished from side to side. He followed her scent to where she had gone back into the brush a minute or so before. He bounded in after her and won her heart for about a week before he vanished. She didn’t seem to mind at all. She went off for about 6 weeks, found herself a male and this past week brought him back to the den area. She’s had three males over the past two months.

That’s typical gray fox behavior at this time of year. Coming up in February they will be settling down with their new mate and have their own litter near the end of March or the beginning of April. The two year olds and older gray foxes will be returning to their traditional den to have another litter. This is going to be interesting because with the female Bold seemingly in possession of her natal den, Squat might return to reclaim it and if so then what might happen down in fox hollow is anyone’s guess.

In my last Fox Report, I mentioned that I would be doing some public presentations – a PowerPoint show with video of the pups taken by my trail cameras – in the coming months. I am scheduled to present one on March 4th at the Redwood City Library for the local Sierra Club. I will send out more detailed information on it soon.

Sleeping Golf Course Fox 4/11/12

Golf Course Fox

Today Bill and I decided to check out the golf course. We went mid-afternoon, not the typical foxing time, and began walking the perimeter of the course. We then entered the golf course nursery, after a few minutes we thought we were out of luck, when we turned to leave we noticed this Gray Fox curled up on a roll of astroturf. We watched from 20 yards as the fox changed positions, yawned, and went to sleep.Sleeping Fox

Foxes can commonly be found in golf courses due to the vegetation and water incorporated into the course and the fox food such as mice, geese and coots that the green grass attracts. Though these courses can offer habitat, one factor against the fox is the common use of Rodenticide to limit the burrowing rodents on the green. Foxes and other predators in turn eat the poisoned rodents and become poisoned themselves. UWRP supports the ban of  rodenticides and urges golf courses to encourage owls and foxes to inhabit the course to control rodents naturally. Live trapping is also an option, one golf course we monitor in Palo Alto uses live traps with flags to alert when the trap has been set off. The foxes there have learned that flag means rodent and the golf course maintenance crew has to change fewer traps. Mother nature is the key, not poison.


Two New Urban Fox Dens 3/30/12

Greg Kerekes ©2012

Today we arrived to the Landfill and got reports from Frank that foxes were seen entering the woodpile multiple days in a row. We checked out the pile and noticed many signs of fox including multiple waterfowl carcasses. The very next day we arrived to the woodpile at sunrise and caught a glimpse of a fox entering the woodpile.

Duck Wing at Woodpile

We arrived to the water plant later in the morning and a plant worker told us that foxes were seen coming in and out of this hole in some roots by their tool shed in the middle of the night. Adjacent to this burrow is a parking lot and multiple buildings with humans working 24hrs a day. This species can tolerate living in close proximity to humans, if their is a secure enough den site and enough foraging habitat.

Greg Kerekes ©2012

Pups got a Gosling 8/15/12

Two Gray Fox Pups 8-15-12
Greg Kerekes ©2012

This morning we were greeted by 2 pups. They emerged from the bunchgrass and posed. They began prancing and chasing each other around Fox Hill. Bill and I searched for new signs of fox activity around the territory. We look for wildlife trails, tracks, scat, cashed food, and animal remains; any clue that might give us an insight into the foxes behavior. Today we found what appeared to be a Gosling carcass. We have had families of Geese appear on our trail cameras within den fox territory recently, looks like the fox sniffed them out. Also found in foxland today was a freshly eaten duck egg and a large piece of tinfoil brought over from the landfill.

Gosling in Fox Land 8-15-12
Greg Kerekes ©2012



Get every new post delivered to your Inbox.