CDFW Expands Statewide Sampling for Chronic Wasting Disease

The California Department of Fish and Wildlife (CDFW) is increasing the scope of its monitoring and testing efforts for Chronic Wasting Disease (CWD) in California’s deer and elk herds.

“While California has never had a report of CWD, increased testing is needed to establish with a high degree of certainty that there are no deer with CWD in California,” said CDFW Wildlife Veterinarian Brandon Munk. “Keeping this disease out of our state is a top priority, both for wildlife managers and for hunters.”

CWD is always fatal to deer and elk, and is an ongoing concern for hunters and managers throughout the country. Once CWD enters a herd, it is nearly impossible to eradicate. Although there are no known cases of CWD being transferred to humans, the Centers for Disease Control and Prevention (CDC) recommends not consuming meat or organs from any animal that tests positive for CWD.

CDFW’s Wildlife Investigations Laboratory has set an ambitious goal to test 600 deer statewide during this year’s hunting seasons and increasing that number to 2,000 statewide in the upcoming years.

Continued hunter cooperation will be key to achieving the CWD deer testing goals. CDFW will set up check stations during the various deer seasons, and hunters will be asked to bring their deer in for the quick removal of a lymph node for testing. CWD testing of hunter-taken deer is voluntary, and no meat is taken.

Information about specific locations and times of operation of CWD check stations in each of the state’s deer zones and control hunt areas will appear on CDFW’s website. Hunters can also contact regional CDFW offices to get check station schedules. Some offices may also offer onsite deer testing.

Some professional meat processors and butchers throughout the state are also partnering with CDFW to take samples from deer at the hunter’s request. Hunters who may be unable to visit a check station or CDFW regional office for sampling are encouraged to ask their butcher ahead of time if sampling is available at the time of processing.


Media Contacts:
Brandon Munk, CDFW Wildlife Investigations Lab, (916) 358-1194
Nathan Graveline, CDFW Big Game Program, (916) 445-3652
Kirsten Macintyre, CDFW Communications, (916) 322-8988


Deadly Bat Fungus Detected in California

The fungus that causes White-nose Syndrome (WNS), a deadly disease of bats, has been detected in low levels in California for the first time. Fungal DNA of Pseudogymnoascus destructans (Pd) was detected in samples collected this spring from bats on private land in the Plumas County town of Chester. The California Department of Fish and Wildlife (CDFW) and U.S. Fish and Wildlife Service (FWS) have been preparing for possible detection of the fungus with partner organizations since 2009. While there is currently no indication the disease itself is affecting bat populations in California, the lab tests suggest Pd is here.

WNS awakens bats during hibernation, causing them to use energy reserves needed to survive winter, when insects they rely upon for food are not available. The fungus was first detected in New York in 2006 and spread incrementally. Bats that have contracted the disease have now been confirmed in 33 states and seven Canadian provinces. Including the recent California discovery, the fungus alone has now been detected in a total of five states.

WNS has killed millions of bats in the U.S., including more than 90 percent of the bats in some hibernation colonies. Since bats usually produce only one offspring per year, it could take decades for some populations to recover from a major die-off.

“WNS is considered one of the deadliest wildlife diseases, having killed over six million North American bats since it was discovered,” said CDFW Wildlife Veterinarian and Epidemiologist Dr. Deana Clifford. “WNS doesn’t affect human health or pets, but the ecological impacts of bat die-offs may indirectly impact agricultural systems through loss of the natural pesticide effect and nutrient cycling of bats.”

Until spring 2016, the westernmost occurrence of Pd was in eastern Nebraska. In March of that year WNS was confirmed in Washington State—1,300 miles west of the nearest known location of the fungus. How it got there is unknown; Pd spreads through physical contact with an infected bat or Pd in the environment. Because spores are persistent, people can also spread the fungus from infected areas to non-infected areas on their shoes, clothes or gear.

Surveillance for WNS has been supported by a national program administered by the U.S. Geological Survey (USGS) National Wildlife Health Center in Wisconsin in collaboration with FWS, Northern Arizona University (NAU), and Bat Conservation International (BCI). CDFW has worked with the National Park Service Klamath Network (NPS KLMN) and others to collect swab samples from bats around California since 2016. The samples tested for the DNA signature of Pd were negative until 2018, when one sample from a little brown bat maternity colony in Chester suggested the fungus may be present at low levels. In 2019, the same site and another in Chester yielded three bats with similar low-level detections.

Dr. Alice Chung-MacCoubrey of the NPS KLMN, who led the surveillance work at Chester and several other northern California sites, said, “The detection of Pd at Chester, even at these low levels, is troubling. It has now been detected in two successive years at two different sites and with testing by both the NWHC lab and the NAU lab. In other parts of North America affected by WNS, low-level Pd detections preceded detection of the disease itself by one to four years.”

“Detection of Pd at the levels reported in Chester are possible thanks to advanced tools and surveillance networks in place today that we did not have in the years right after WNS was discovered,” said Jeremy Coleman, National White-nose Syndrome coordinator for the FWS, which leads the national response to the disease. “These very early indications that Pd is present allow for a more proactive response by local partners than what has been possible before. Just how long we’ll have before WNS emerges in California’s bats is a big unknown.”

CDFW leads the California WNS Steering Committee, a multi-agency scientific research group that has been monitoring WNS nationally since 2009. The Committee includes the FWS, NPS, U.S. Forest Service, USGS, BCI, California State Parks, U.S. Department of Defense and National Speleological Society (NSS). They developed a WNS response plan for California that outlines actions to be taken if the fungus or disease arrives in California.

“It is critically important for CDFW and our partners to follow up on these detections,” said CDFW Wildlife Ecologist Dr. Scott Osborn. “In the coming months and years, we will intensify surveillance for WNS, monitor impacts on bat populations, and assist with research on disease management. We hope disease treatment and prevention techniques currently in development will be available soon.”

Meanwhile, Osborn asks all Californians to be vigilant and cooperate with management actions that may be taken to slow the spread of WNS. People can assist with surveillance by reporting unusual behavior they see in bats. Sick or dying bats observed during winter in the colder regions of the state should be reported to CDFW at

According to Osborn, caving organizations like the NSS have helped collect important information about California’s underground bat roosts. People who enter caves and mines should follow decontamination protocols at, and do not transfer clothing or gear between certain sites.

Details about WNS and Pd are at

For photos and B-roll video, visit the White-nose Syndrome National Response Team newsroom at

Information about bat conservation is available at

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Featured image (above): Hibernating, healthy little brown bat by Ann Froschauer/USFWS

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Media Contacts:
Scott Osborn, CDFW Nongame Wildlife Program, (916) 324-3564
Catherine Hibbard, USFWS National WNS Response Team, (413) 531-4276
Dana Michaels, CDFW Communications, (916) 322-2420

Bighorn sheep ram

CDFW Investigating Die-Off of Desert Bighorn Sheep

Wildlife biologists from the California Department of Fish and Wildlife (CDFW) are investigating what appears to be a significant mortality event associated with respiratory disease among the San Gorgonio desert bighorn sheep population in Riverside County. CDFW has confirmed that at least 20 animals have died but suspects that total mortality may be greater.

“The significance of this outbreak to the San Gorgonio desert bighorn sheep population is being investigated,” explained Heidi Calvert, an environmental program manager with CDFW’s Inland Deserts Region. “Our top priority right now is to determine the source and nature of the disease so that we can identify the right management actions to mitigate future risk.”

CDFW staff began receiving reports of sick desert bighorn sheep in December 2018 and immediately began collecting samples for lab analysis. CDFW is continuing to survey and monitor the population to gather more information on the extent and magnitude of this loss to the population. Private landowners and partner agencies are assisting with this effort.

The Western Association of Fish and Wildlife Agencies Wild Sheep Working Group considers respiratory disease to be “the biggest impediment to restoring and sustaining bighorn sheep populations.” Respiratory disease in bighorn sheep is most commonly attributed to contact and/or proximity with domestic sheep and, to a lesser extent, domestic goats. Diseases that originate with domestic animals can pose a significant risk to bighorn sheep populations.

The affected desert bighorn population is located within Desert Bighorn Sheep Hunt Zone 5. The recent die-off will likely result in reducing the two hunting tags to zero in this zone for 2019.


Media Contacts:
Heidi Calvert, CDFW Inland Deserts Region, (760) 872-0751 

Kirsten Macintyre, CDFW Communications, (916) 322-8988

DFG Continues Investigation of Western Grey Squirrel Deaths

 Media Contacts:
Jeff  Villepique, DFG Wildlife Biologist, 760-937-5966
Janice Mackey, DFG Communications, 916-322-8908

Residents of
San Bernardino Mountains Asked to Help Collect Information

Last spring, the California Department of Fish and Game (DFG) received reports from residents of sick and dying western gray squirrels in Big Bear Valley. 

Researchers from DFG, the California Animal Health and Food Safety Lab in

Western Grey Squirrel

San Bernardino, and University of California, Davis, School of Veterinary Medicine concluded the squirrels were dying from complications of mange, a contagious skin disease caused by parasitic mites that burrow into the skin of affected animals, causing intense itching and infection. 

Surveys conducted in spring of 2012 yielded only a handful of western gray squirrels in areas of the Big  BearValley where squirrels were once plentiful.

Local residents are now being asked to help collect data so researchers can better understand past abundance, where sick squirrels have been observed, and where western gray squirrels are now. The website address to report information is at:

Information provided by the public will help construct a picture of what happened to the squirrel population in the San Bernardino Mountains and help track the pace of their re-growth. In addition, this information will also help researchers determine whether conservation measures can be taken to prevent further loses of squirrels.

The species of mange mites affecting gray squirrels, Notoedres centrifera, is specific to rodents and cannot infect humans or pet cats and dogs. Veterinary researchers caution residents that local wildlife, including coyotes, raccoons and bobcats often carry other species of mange that can infect their pets and, rarely, people. If your pet scratches excessively or develops scabs, you should seek veterinary care as symptoms could be from one of the other forms of mange, which are readily treatable.

DFG Investigates First Cases of Canine Distemper in Wild Desert Kit Foxes

Desert kit fox
Desert kit fox with radio collar

Andrew Hughan, DFG Communications, (916) 322-8944
Deana Clifford, DFG Wildlife Veterinarian, (916) 358-2378
Erin Curtis, Bureau of Land Management, (916) 978-4622

The Department of Fish and Game (DFG) is investigating the death of seven desert kit foxes from canine distemper in eastern Riverside County. These deaths, which occurred over the past two months, are the first documented cases of canine distemper in wild desert kit foxes. Wildlife officials want to determine if this is an isolated case or if the disease is more widespread.

The kit foxes were found 20 miles outside of Blythe on public lands managed by the Bureau of Land Management (BLM) and leased to Genesis Solar LLC to construct a utility-scale solar project. The animals were turned over to DFG’s wildlife investigations lab for testing. The necropsies determined that distemper was the cause of death, but it is not known how the foxes contracted the disease. Canine distemper can cycle naturally in wild carnivore populations, but can also be transmitted to and from domestic animals that come in contact with wildlife.

“Although we do not know if this outbreak was started by an infected domestic animal, it is important for people to vaccinate their pets regularly,” said DFG Wildlife Veterinarian Deana Clifford. “Vaccination will not only protect your pet but help protect wildlife populations from disease outbreaks.”

To better understand the extent of the disease, how it was contracted and how to prevent it, wildlife officials trapped, tested and tagged 39 foxes. Researchers also attached radio collars to 12 of these foxes in order to obtain health information for the study. These collars are equipped with a mortality signal that pulses twice as fast as normal if the animal has not moved for six hours. This allows researchers to detect a death and quickly recover the carcass. Biologist and volunteers will be using the radio signals and remote triggered cameras to monitor dens during the upcoming pupping season.

In addition, a subset of 27 kit foxes received a distemper vaccine and were released back into the wild. Researchers hope this vaccine, specifically developed for use in species that are very sensitive to the virus, will create an immune response in the desert kit fox population.

The desert kit fox, found in the southeastern deserts of California, can survive in dry climates because it obtains all its water from food sources. Its more northern relative, the San Joaquin kit fox, is listed as endangered under both state and federal endangered species acts due to loss of habitat and other factors.

“Even though the desert kit fox is not endangered, it is a uniquely adapted species that deserves monitoring and conservation attention,” said DFG Environmental Scientist Magdelena Rodriguez. “We are building strong relationships with our partner agencies and other stakeholders working in the desert to better conserve kit fox populations.”

DFG is coordinating its efforts with the California Energy Commission, who is the state permitter for the solar project, and the U.S. Bureau of Land Management. Construction in the area has been temporarily halted, in part due to the kit fox distemper discovery.

“We are working closely with the company in an effort to avoid additional impacts to desert kit foxes in areas where construction is under way,” said BLM’s Palm Springs Field Manager John Kalish.