Death of Silicon Valley Grey Foxes Point to Urgent Need for Wildlife Corridors

DNA bottlenecks, inbreeding make animals susceptible to disease, says “Fox Guy”

Tom Molanphy

Bill “Fox Guy” Leikam hopes the most recent chapter in the story of the Silicon Valley urban fox is not the beginning of a tragedy for connecting healthy ecosystems. As reported by the San Jose Mercury News last week, up to 18 urban gray foxes belonging to four different “skulks,” or groups, that Leikam has studied and researched over the last seven years in Palo Alto, California, died last month of canine distemper – a contagious viral infection with no known cure.

photo © Bill Leikam

This is the first time in recent memory that local wildlife observers have seen such a big wildlife die-off. “We have 12 fox carcasses and six more that are missing and presumed dead,” Leikam, , founder of the Urban Wildlife Research Project, told Earth Island Journal . “[December] was like a dark wind carrying the virus as it swept through, taking all of the foxes throughout the region and possibly even up into East Palo Alto. “

The gray fox, a small, tree-climbing member of the canid family, is one of the few wild carnivore species that seems to have successfully adapted to living in and around big cities, though it still faces many threats. A small population of these urban-dwelling canids, comprising several skulks, have captured the hearts of residents and researchers in California’s Silicon Valley, including Leikam who has been researching their role in the local ecosystem as well as the challenges urban habitats present to grey foxes.

It’s hard to pin down the exact number of foxes living in the South Bay Area. Leikam says they seem to be living in “pockets” and regions from south Redwood City, south through Alviso and up the eastern side of the Bay to at least the southern edge of the Oakland International Airport. They have also been spotted in the foothills of Los Altos, Saratoga, and on south.

photo © Bill Leikam

Watching animals die from distemper – especially animals you have studied and protected and know by name – is not something “I ever want to live through again,” said the retired schoolteacher whose dogged monitoring of the foxes earned him the “Fox Guy” moniker.

Unlike animals with rabies who turn aggressive, animals with canine distemper turn incredibly lethargic. “They won’t even move out of way,” Leikam said. “The distemper attacks their respiratory, nervous, immune and gastrointestinal systems and their brains swell. During the last stage before their systems collapse, which has been documented, they walk around as if they’re drunk…. and within half an hour they’re dead.”

All roads from this local catastrophe lead to the urgent need for nature corridors as well as the overall understanding of ecosystem connectivity, said Leikam, who hopes to eventually help create a comprehensive “San Francisco Bay Area Wildlife Corridor” that would protect this region’s rich natural heritage. Leikam hopes the decimation of this urban fox population can vault the subject of nature corridors into more mainstream circles. “It’s all happening in our backyards. We just need to be a little more attentive about what is happening with the wildlife around us.”

The basic idea for wildlife corridors has been around for some time, most noticeably – and dramatically – promoted by renowned scientist E.O. Wilson and his notion of a “Half-Earth,” i.e., the need to dedicate a full half of Earth to natural systems in order to help species survive and thrive. One of the most prominent organization promoting ecosystem connectivity is the Yellowstone to Yukon Conservation Initiative, the nonprofit that has been working to connect Yellowstone to Yukon since 1997.

”It makes sense that when animals are in an “island” and inbreeding occurs, that the genetic pool becomes degraded and the immune system grows weak,” Leikam said. “It’s easier for distemper to attack. But once you open up the corridor, that increases genetic diversity, which in turn increases the body’s ability to fight disease.”

Although the range of the Palo Alto urban foxes is much smaller than the area encompassed by the Yellowstone to Yukon proposal, the principles remain the same – wild animals need to able to travel between habitats. One big difference, as any living creature in the Bay Area knows, is that this space is coveted by many different interests. Put the needs of a small canine up against the financial interests of a billion-dollar developer, and you can start to understand the battles Leikam has faced over the years.

David Johns of the Wildlands Network, a conservation group that’s pushing for the creation of a network of wildlife corridors or “wildways” across North America,

has been an avid supporter of nature corridors and overall connectivity for some time. ”The important larger message here is the loss of habitat,” Johns said. ”These foxes are on the edge and it doesn’t take much to push them over that edge.”

Add into that the real possibility of a federal government that will be, at best, totally disinterested in urban wildlife and, at worst, hell-bent on defunding every policy that has the word “environmental” anywhere near it, and it’s not hard to understand the depths of Leikam’s concern. “It’s all speculation at this point… but some of the [federal] cabinet appointees to some of the conservation areas seem to back oil companies more than conservation,” he said.

Both Leikam and Johns are part of a long environmental movement that have asked simple but essential questions, such as: What if the policies, laws and guidelines that regulate human behavior were based on long-term, environmentally sustainable stewardship instead of short-term, profit-driven projects?

photo by Jeffrey Ferland

For now, Leikam plans to press on. He did spot a few “skittish” foxes last week – young, first year, gray foxes dispersing from their birth areas to establish their home range and find a mate. Leikam even checked in with the Facebook campus in Menlo Park. A family of foxes that has adopted the campus as home and has taken on rock-star status, and was happy to find out that “the foxes there look as normal as can be.”

But the long-term sustainability of the urban fox will involve a coordinated effort to promote – and a broad understanding to accept – the notion that such wildlife not only poses no threat to humans, but that they can provide benefits such as rodent control, as well.

”What we need most is funding for our DNA project.,” Leikam said. “That project will help us identify relationships between the urban foxes and find out exactly where the inbreeding has happened. Since this population has been wiped out, we’ll have to move into new areas to do that DNA work, as well as continue our study at the Palo Alto Baylands Preserve.” he said. “We’re moving forward.”