The Wildlife Society has published an article highlighting our collaborative work to understand and combat the emergence of mange in endangered San Joaquin kit foxes.
A Los Angeles Times article released today highlights three Mojave species vulnerable to increasing drought and the long term impacts of climate change.
The CDFW WIL is part of the inter-agency-academia team helping to recover Amargosa vole populations.
Click here to read the article and watch a video of our UC Davis partner, Professor Janet Foley, explaining the plight of the vole and demonstrating how we work with voles.
Originally posted on CDFW News:
Media Contacts: Janice Mackey, CDFW Communications, (916) 322-8908 Deana Clifford, Wildlife Investigations Lab, (916) 358-2378 Researchers Follow Up on 2012 Distemper Outbreak The California Department of Fish and Wildlife (CDFW) has completed the second year…
The western pond turtle (Emys marmorata), the only native species of freshwater turtle in California, has been a species of special concern since 1994. Possible causes for declining western pond turtle populations include urbanization and habitat destruction (which often reduces or eliminates basking and nesting sites available near pond
habitat), poor water quality, and reduced survival of young turtles causing the population to be skewed towards aged turtles that don’t reproduce well.
Another challenge to the survival California’s native western pond turtles has been the introduction and spread of non-native red-eared sliders (Trachemys scripta elegans). Red-eared sliders were imported for the live food market and are popular in the pet industry, often resulting in illegal pet release. “Sliders” are larger than pond turtles
and outcompete pond turtles for nesting and basking sites.
It is not known if disease is playing a role in the observed declines of western pond turtles. Additionally, introductions of non-native red-eared sliders into pond turtle habitat might also introduce new pathogens (disease causing agents like viruses, bacteria, fungi, and parasites) or strains of pathogens that western pond turtles had not been previously exposed to.
Absolutely nothing was known about the pathogens western pond turtles are exposed to in California, so Janet Foley, Joy Worth and then Master’s student, Connie Silbernagel from UC Davis School of Veterinary Medicine, Deana Clifford from the CDFW Wildlife Investigations Lab, and Jamie Bettasco from the US Fish and Wildlife Service teamed up to conduct the first assessment of pathogen presence in western pond turtles across the state. The team also tested non-native red-eared sliders at study sites where both species were living to see whether or not red-eared sliders carried different pathogens and whether or not western pond turtles living in the same sites as nonnative sliders were more likely to carry different pathogens.
The team found that both species of turtles carried Mycoplasma spp. bacteria (a cause of respiratory infections) with prevalence being highest at sites in southern California regions. Furthermore native western pond turtles that were infected with Mycoplasma spp bacteria were more likely to weigh less and live in southern California. All turtles tested negative for two common viruses, Herpesviruses and Ranaviruses, and Salmonella bacteria (which can cause gastroenteritis and is a bacteria that can infect people).
This study is the first of its kind to document pathogen prevalence in both native western pond turtles and non-native red-eared sliders and will provide important baseline data as we strive to conserve western pond turtles in California.
Silbernagel C, Clifford DL, Bettaso J, Worth S, Foley J. Prevalence of selected pathogens in western pond turtles and sympatric introduced red-eared sliders in California, USA. Diseases of Aquatic Organisms 107:37-47
A team from UC Davis–the UC Davis California Animal Health and Food Safety Lab (CAHFS), CDFW veterinarians Pam Swift and Deana Clifford, and CDFW biologist Jeff Villepique–describe the findings from a notoedric mange outbreak that occurred in 2009 and was thought to be responsible for a significant decline in the number of Western Gray Squirrels in the mountain communities of San Bernardino County.
The team found that mange infections were quite severe for the affected squirrels, and confirmed through electron microscopy and molecular methods that the mite making squirrels sick was a species called Notoedres centrifera, a mite known to have caused outbreaks in other western gray squirrel populations.
CDFW and UC Davis are continuing to monitor the western gray squirrels in this area using a citizen science website where people can report sightings of both sick and healthy squirrels.
Pathologic findings in Western gray squirrels (Sciurus griseus) from a notoedric mange epidemic in the San Bernardino Mountains, California
Nicole Stephenson, Pam Swift, Jeffrey T. Villepique, Deana L. Clifford, Akinyi Nyaoke, Alfonso De la Mora, Janet Moore, and Janet Foley. 2013. International Journal for Parasitology. Volume 2, Pages 266–270.
In only 19 square kilometers of the Amargosa basin in the Mojave Desert of California, lives the small, brown Amargosa vole (Microtus californicus scirpensis). This specialized vole lives in bullrush (Scirpus oleyni) dominated marshes that appear when the normally underground Amargosa river reaches the surface. Conservation of this unique habitat on which this state- and federally-listed endangered vole depends has been a cornerstone of conservation efforts.
While conducting surveys to determine for Amargosa Voles in September 2010, California Department of Fish and Wildlife scientist Tammy Branston discovered unusual deformities on the ears and genitalia of some of the voles which appeared to be associated with the presence of an orange substance on the skin. Some voles were so severely affected that they were missing their ear pinnae (the visible part of the ear) altogether. Tammy alerted CDFW veterinarian Dr. Deana Clifford, and along with her colleagues Dr. Janet Foley, a small mammal disease ecologist at UC Davis, and Dr. Leslie Woods, a veterinary pathologist at the California Animal Health and Food Safety Lab (CAHFS) at UC Davis, they sampled affected voles and conducted additional tests to determine the cause of the deformities. They discovered that the orange “stuff” was actually a hard orange mite, a chigger in fact. Of 151 Amargosa voles examined from February-April of 2011, 40% of the voles had hard orange mites adhered to some part of their bodies, and 47% of voles examined had ear lesions and deformities which included alopecia (hair loss), swelling, tissue death and ulcers at the ear edges, as well as scarring, scabbing, and loss of external ear tissue.
The team’s findings are published in the August 2013 issue of the Journal of Parasitology.
It is extremely unusual to see such severe damage due to a chigger in a small mammal, which raises concerns that this condition could negatively impact the health and fitness of individual voles.
An interdisciplinary team with members from CDFW, UC Davis, UC Berkeley, the Bureau of Land Management, the US Geological Survey, and the US Fish and Wildlife Service, is studying population dynamics, habitat needs, genetics, and disease in order to ensure that healthy populations of this unique endangered vole of the desert persist well into the future.
Full reference: 2013. Foley J, Branston T, Woods L, Clifford D. Severe ulceronecrotic dermatitis associated with mite infestation in the critically endangered Amargosa vole (Microtus californicus scirpensis). Journal of Parasitology. Aug;99(4):595-8.
The WIL’s nongame wildlife veterinarian, Deana Clifford, has coauthored an article describing the impacts of illegal marijuana cultivation on wildlife.
Dr. Clifford and her co-authors are members of a multidisciplinary, multi-organizational working group advocating a strong science-based approach to assessing the impact of illegal cultivation on public lands.
The article entitled “Silent Forests? Rodenticides on Illegal Marijuana Crops Harm Wildlife” appears in the current issue of The Wildlife Professional magazine published by The Wildlife Society (TWS).
by Deana Clifford
If I were to write an job advertisement, it might read something like this…
“Highly motivated individual needed to climb up and down unstable rocks all day at high elevation in an effort to study a very charismatic, but highly elusive small mammal.
Additional Qualifications: Must not be afraid of heights!”
What am I talking about? Studying pika of course!
Although American pikas (Ochotona princeps) may look a bit like a hamster or guinea pig, they’re actually most closely related to rabbits and hares. Pikas live in alpine terrain above the tree line. In California they are found at moderate to high elevations in the southern Cascades, Sierra Nevada and mountain ranges of the Great Basin. They live on rock-laden slopes called talus, and eat grasses, plants and wildflowers.
Pikas are charismatic. They are often seen or heard by hikers when they are defending their rocky territory. (Click here to watch video of a a pika calling.)
Habitat loss has caused the disappearance of some pika populations, but climate change is considered to be the primary threat to the long-term persistence of pika populations in California. Mining, grazing, disease and other factors may also impact pikas.
As part of my job as the Department of Fish and Game’s wildlife veterinarian for nongame species, I have been working with Dr. Janet Foley at UC Davis to study the health of pikas since 2010. Our goal is to find the best method to safely work with pikas and to determine which diseases could be a threat to pika populations by understanding what diseases are already present in pika populations.
In order to study the biology of pikas and evaluate threats to pika populations, we need to trap and examine individual pikas.
This is more challenging than one might think. Although it is relatively easy to see and hear pikas while on the talus, they are not particularly interested in entering a box trap for food. Also, since pikas live in remote areas, our teams often have to backpack into their habitat to study them.
Accomplished pika researcher Dr. Chris Ray at University of Colorado-Boulder has given us sage advice on how to lure pikas into our traps.
Although we were not successful at trapping pikas during our two short trips this summer, we were able to examine and sample other small mammal species that live in and near the pika’s habitat.
Determining which diseases are present in other small mammal species that border or overlap with pika populations will provide important information about the diseases pika may be exposed to.
Even though studying pika might be considered extreme field work, the effort is worthwhile because it gives us the chance to see this incredible animal and to gather information to inform future conservation efforts.
We will be back climbing the talus next summer!
This project has been one of the research endeavors fostered by the California Pika Consortium (CPC). The CPC is an interdisciplinary collaborative effort that fosters research, monitoring, education, conservation and adaptation planning for pikas and other high-elevation species.
To learn more about the work of the California Pika Consortium, the National Pika Consortium, and to find additional resources about pika conservation and biology click here.
***Dr. Deana Clifford is the Department of Fish and Game’s wildlife veterinarian and epidemiologist for nongame, threatened and endangered species.