WERC Highlights -- February 2008

Reducing Catastrophic Fires in California: USGS fire ecologist Jon Keeley has been invited by the California Legislature Senate Natural Resources and Water Committee to participate as a panelist for a joint informational hearing titled “Can Improved Fire Prevention Reduce Catastrophic Fire Risks in California?”, to be held March 7 at 1 p.m. at San Diego State University, San Diego, CA. Keeley will be first speaker in the opening panel topic “Status of Fire Threat in California.” Keeley will discuss future fire regimes in California and how we can reduce the impacts of catastrophic fire through better land planning and altering human infrastructure, emphasizing the need for society to prepare for fires much like we do for other natural hazards such as earthquakes. (Jon Keeley, Three Rivers, CA, 559-565-3170).

Mercury Contamination and Shorebird Chick Survival: American avocets and black-necked stilts forage and nest in shallow-water wetland habitats along South San Francisco Bay’s margins where methymercury production is relatively high. In a recent study by the USGS and U.S. Fish and Wildlife Service, scientists used radio telemetry to estimate chick survival in relation to mercury concentrations in down feathers at hatching, which are an index of a chick’s whole-body burden of mercury at hatching. The researchers also compared mercury concentrations in chicks that were found dead at colonies to those in randomly sampled live chicks of similar age. Although they found no effect of mercury on chick survival from hatching to fledging, they found that mercury concentrations in down feathers of dead chicks were higher than those in randomly-sampled live chicks. Citation: Ackerman, J.T., J.Y. Takekawa, C.A. Eagles-Smith, and S.A. Iverson. 2008. Mercury contamination and effects on survival of American avocet and black-necked stilt chicks in San Francisco Bay. Ecotoxicology 17:103-116. (Josh Ackerman, Davis, CA, 530-752-0485)

Climate Change Research: The Associated Press reported Feb. 26 in the San Jose Mercury News on climate change research in the southern Sierra Nevada by USGS, U.S. Forest Service, Sequoia and Kings Canyon National Parks, and Giant Sequoia National Monument, and a symposium these agencies will hold in the fall about global warming’s impact on snowpack, water tables, and other natural features. See: http://www.mercurynews.com/news/ci_8371525.

Mountain Yellow-legged Frog: USGS scientist Robert Fisher was interviewed for a March 2 story in the Fresno Bee about the Fresno Chaffee Zoo and its director of animal care and conservation, which are involved in the conservation program to restore populations of endangered mountain yellow-legged frogs in southern California, and about zoos worldwide making amphibians a high conservation priority during this leap year, which has been designated Year of the Frog. See: http://www.fresnobee.com/263/story/435537.html.

Frogs: USGS scientist Gary Fellers provided frog/habitat photos for a textbook on population biology modeling, and frog photos to the Stockton Record.

Postfire Vegetation: USGS scientist Jon Keeley was interviewed for a Feb. 24 story in the San Diego Union-Tribune on recovery of southern California areas burned in 2007, the rapid germination of nonnative plants following postfire rain, and the potential for conversion from native vegetation to alien grasslands where fires burned in both 2003 and 2007. See: http://www.signonsandiego.com/news/metro/20080224-9999-1m24recover.html.

Canine Teams as Effective as Human Teams in Detecting Desert Tortoises in the Wild: Properly trained wildlife detector dog teams offer a safe, quick, and effective alternate means for conducting field surveys of adult desert tortoises in the Mojave Desert, according to a new study by the USGS, University of Nevada, Reno, Desert Research Institute, and Applegate School for Dogs. Desert tortoises are cryptic and can be hard for humans to visually detect under natural conditions, especially small tortoises. Wildlife detector dogs rely on smell over visual cues to find tortoises. The researchers conducted comparative surveys to determine whether human or detector dog teams were more effective at locating desert tortoises in the wild and then compared costs to deploy dog rather than human teams. There was statistically no difference between human and dog team detection, both with estimates at about 70 percent probability of detection. The dog teams finished the daily surveys in 66 percent of the time required by humans; the human teams cost 60 percent as much as the canine teams. Dogs found a greater proportion of tortoises located in vegetation than did humans, but neither dogs nor humans detected appreciable numbers of small tortoises. Additional focus on training and adjustments in search strategy might increase dog team detection rates of smaller size classes of tortoises, greatly improving the technique. These findings may be of benefit to both research and conservation of desert tortoises given the increasing demand for field surveys as a result of monitoring and clearances of desert tortoises for urban and other development. The article and an associated photo gallery can be viewed at: http://www.herpconbio.org/Volume_3/Issue_1/V3_I1_Contents.htm. (Ken Nussear, Henderson, NV, 702-564-4515) Citation: Nussear, K. E., T. C. Esque, J. S. Heaton, M. E. Cablk, K. K. Drake, C. Valentin, J. L. Yee, and P. A. Medica. 2008. Are wildlife detector dogs or people better at finding desert tortoises (Gopherus agassizii)? Herpetological Conservation and Biology 3(1):103-115.

New Study Finds Significant Decline in Cascades Frog at Southernmost Part of Its Range: According to a new assessment of its status in the vicinity of Lassen Peak in northern California, the Cascades frog (Rana cascadae) has declined significantly from 1993 to 2007. To assess the status of this once common frog of the Lassen region, researchers from USGS, USDA Forest Service, and the University of California at Davis and Berkeley used data sets from four extensive frog surveys that had been conducted from 1993 to 2007 in Lassen National Forest and Lassen Volcanic National Park, subsequent to USGS work published in 1993. Frogs were located at only six sites in the study area, and no more than 10 adults at any of the sites. Causes for the decline remain unclear, but introduced trout, disease, and pesticides are likely factors. Their findings were recently published in Herpetological Conservation and Biology. The article and an associated photo gallery can be viewed at: http://www.herpconbio.org/Volume_3/Issue_1/V3_I1_Contents.htm. (Gary Fellers, Point Reyes, CA, 415-464-5185) Citation: Fellers, G. M., K. L. Pope, J. E. Stead, M. S. Koo, and H. H. Welsh, Jr. 2008. Turning population trend monitoring into active conservation: Can we save the Cascades frog (Rana cascadae) in the Lassen Region of California? Herpetological Conservation and Biology 3(1):28-39.

Novel Patterns of Historical Isolation, Dispersal, and Secondary Contact Across Baja California in the Rosy Boa: The geological and ecological events associated with the formation of Baja California and surrounding North American deserts, shaped the distribution and evolution of lineages of the rosy boa (Lichanura trivirgata), according to a new genetics study by USGS and San Diego State University scientists published in Molecular Phylogenetics and Evolution. The geographic range and ecological constraints of this species provided a unique opportunity for testing population differentiation hypotheses across significant biogeographic boundaries important in Baja California and the southwestern region of North America. The researchers detected three genetic lineages within the species, with very little geographic overlap. Two lineages were predominately separated along the Colorado River and are found primarily within California and Arizona, while a third lineage consisted of disjunct groups distributed along the Baja California peninsula, south-central Arizona and southward along the coastal regions of Sonora, Mexico. Estimated time points of earliest divergence and geographic congruence of barriers to gene flow between lineages, suggest early extensions of the Gulf of California and subsequent development of the Colorado River during the Late Miocene-Pliocene (7-4 million-years-ago) led to the formation of these genetic lineages. Their genetic data also support a relatively novel pattern of trans-gulf (over-water) dispersal for Baja California and Sonoran populations, possibly using a partial land bridge of islands in the Gulf of California. The authors also discussed genetic and morphological evidence in support of recognizing two species within the genus Lichanura. (Dustin Wood, San Diego, CA, 619-225-6432) Citation: Wood, D. A., T. W. Reeder, and R. N. Fisher. 2008. Novel Patterns of Historical Isolation, Dispersal, and Secondary Contact Across Baja California in the Rosy Boa (Lichanura trivirgata). Molecular Phylogenetics and Evolution 46:484-502.

Warming Mountains: USGS scientist Nate Stephenson was interviewed on Feb. 19 by the Fresno Bee for an upcoming article on the effects of climatic changes on California's Sierra Nevada.

Elephant Seals: USGS scientist Brian Hatfield was interviewed on Feb. 19 by Fox News for a story on elephant seals straying across a California highway.

Blackbrush: USGS scientists Sara Scoles and Anine Smith were interviewed for a Feb. 12 story in the Desert Valley Times (Mesquite, NV) about a project in which BLM, in partnership with USGS and helped by volunteers, is trying to re-establish native blackbrush in several burned areas of southern Nevada. See: “Volunteers help bring back life to scorched desert” at http://www.dvtnv.com.

Elephant Seals: USGS scientist Brian Hatfield was interviewed for a Feb. 15 NPR California Report story about elephant seals escaping the protective fencing that separates their rookery at a Piedras Blancas beach from busy California Highway 1.

Scientists Receive the Desert Tortoise Council's 2007 Annual Research Award for Their Genetics Research: Scientists Robert Murphy (Royal Ontario Museum), Kristin Berry (USGS), Taylor Edwards (University of Arizona), and Ann McLuckie (Utah Division of Wildlife Resources) will be recognized as winners of the 2007 Annual Research Award by the Desert Tortoise Council at their 33rd Annual Meeting and Symposium, Feb. 22-25, in Las Vegas, NV. The award to these four scientists recognizes the culmination of several years of combined research. Their most recent work, which was recently published in Chelonian Conservation and Biology, assesses the validity of six recovery units established for the desert tortoise in the 1994 Recovery Plan for the Mojave population of the desert tortoise. These recovery units were delineated using the best available data on habitat use, behavior, morphology, and genetics. The team of scientists analyzed new genetic data by using mitochondrial DNA sequences and nuclear DNA microsatellites from desert tortoises sampled in all recovery units and desert regions throughout the Mojave Desert in California and Utah, and the Colorado Desert of California. Their analyses indicate that the Western Mojave Recovery Unit should be subdivided into three regions (western, central, and southern) with corresponding recovery units (Western Mojave, Central Mojave, and Southern Mojave). These findings and other papers will be presented during the meeting in Las Vegas. (Kristin Berry, Moreno Valley, CA, 951-697-5361) Citation: Murphy, R. W., K. H. Berry, T. Edwards, and A. M. McLuckie. 2007. A Genetic Assessment of the Recovery Units for the Mojave Population of the Desert Tortoise, Gopherus agassizii. Chelonian Conservation and Biology 6:229-251.

New Decision Support Tool for Selecting Translocation Areas for Mojave Desert Tortoises: Approximately two-thirds of the training area expansion of the National Training Center at Fort Irwin, California, encroaches into critical habitat designated for the desert tortoise in the Western Mojave Recovery Unit. The most challenging mitigation measure to implement is the translocation of an estimated 2,000 desert tortoises from portions of the expansion area. A collaborative effort bringing together geospatial, desert tortoise, and management expertise has resulted in the development of a consensus translocation decision support model that has identified six potential translocation areas. This work, in which USGS scientists participated, provided an objective, open, scientifically credible process that ranked translocation suitability by consensus on habitat and conservation-based criteria, and produced seven alternative translocation scenarios from which a single best consensus translocation model was generated. In addition to selecting potential translocation areas, this decision support system can also be used for other desert tortoise management and mitigation needs, particularly for additional decision making, adaptive management and/or evaluation of criteria affected by management decisions. USGS scientists and their coauthors at the University of Redlands and University of Nevada, Reno, recently published this study in the online edition of Biodiversity and Conservation. (Ken Nussear, Henderson, NV, 702-564-4515). Citation: Heaton, J. S., K. E. Nussear, T. C. Esque, R. D. Inman, F. M. Davenport, T. E. Leuteritz, P. A. Medica, N. W. Strout, P. A. Burgess and L. Benvenuti. 2008. Spatially explicit decision support for selecting translocation areas for desert tortoises. Biodiversity and Conservation; doi: 10.1007/s10531-007-9282-3.

Desert Tortoise Research and Management: USGS scientists are participating as symposium and session chairs, keynote speaker, and presenters of over a dozen papers on desert tortoise research at the 33rd Annual Meeting and Symposium of the Desert Tortoise Council, to be held Feb. 22-25, 2008, in Las Vegas, Nevada. The meeting brings together land managers and scientists from federal, state, university, and nongovernmental organizations to discuss issues, research, and management of the desert tortoise in the southwestern deserts. USGS scientists from multiple disciplines will be presenting research papers on a wide array of issues including climate change, plant invasions, fire, contaminants, and disease. Steven Schwarzbach, director of the USGS Western Ecological Research Center (WERC), will deliver the keynote address on how the new USGS science strategy will affect desert tortoise research. USGS WERC scientist Kristin Berry is symposium chair. For more: http://www.deserttortoise.org/symposia.html. (Kristin Berry, Moreno Valley, CA, 951-697-5361)

USGS scientist to Speak on Yosemite’s Rare Plants: On February 14, USGS botanist Alison Colwell will present a slide program, “Rare Plants of Yosemite,” featuring the recently discovered Yosemite bog-orchid, at the Yosemite Area Audubon Society meeting in Mariposa, California. (Alison Colwell, El Portal, CA, 209-379-1308)

Climate Warming: USGS scientist Nate Stephenson was interviewed for a Feb. 4 High Country News story about the challenges public land managers face in managing wildlands and wildlife in an age of global warming. See: http://www.hcn.org/servlets/hcn.Article?article_id=17481.

Elephant Seals: USGS scientist Brian Hatfield was interviewed for a Feb. 4 Los Angeles Times story about elephant seals escaping the protective fencing that separates their rookery at a Piedras Blancas beach from busy California Highway 1. See: http://www.latimes.com/news/local/la-me-seals4feb04,1,4556426.story.