WERC Highlights -- August 2006

Ducks’ Risk-taking Behavior Linked to Differences in Life History Characteristics: Life history may be an important component influencing the susceptibility of waterfowl to harvest, according to a recent study published in the Condor by USGS scientist Josh Ackerman of the Western Ecological Research Center and University of California-Davis collaborators John Eadie and Tom Moore. They investigated the risk-taking behavior and life-history characteristics of seven species of dabbling ducks by measuring their approach behavior – behavior of ducks when approaching potential landing sites – during the waterfowl hunting season. The authors found that approach behavior of ducks was strongly correlated with their life-history characteristics. Species characterized by a “slow” life-history strategy (e.g., northern pintails and mallards, which are less fecund but longer-lived) were more risk-averse than species with a “fast” life-history strategy (e.g., cinnamon teal and green-winged teal, which are more fecund but shorter-lived). Results of the study indicate that life history influences the risk-taking behavior of dabbling ducks and provides an explanation for the differential vulnerability of waterfowl to harvest. For more: http://www.werc.usgs.gov/pubbriefs/ackermanpbaug2006.html. Citation: Ackerman, J. T., J. M. Eadie, and T. G. Moore. 2006. Does life history predict risk-taking behavior of wintering dabbling ducks? Condor 108:530–546.

Tortoise/Turtle Workshop for Wildlife Rehabilitators: USGS scientist Kristin Berry of the Western Ecological Research Center is presenting a workshop on August 26, 2006, on Protocols for Evaluating Desert Tortoises for Rehabilitation, A Model for other Chelonians, at the Annual Symposium for the California Council For Wildlife Rehabilitators. The symposium will be held at The Living Desert Zoo and Gardens in Palm Desert. (Kristin Berry, Moreno Valley, CA, 951-697-5361, kristin_berry@usgs.gov)

Factors Influencing Cowbird Parasitism of Least Bell’s Vireos: Brood parasitism by brown-headed cowbirds reduces the reproductive success and productivity of least Bell’s vireos, a federally endangered subspecies of Bell’s vireo. USGS scientists Barbara Kus and Brian Sharp examined the relationship of vegetation structure surrounding nests and of vireo behavior near nests to the incidence of parasitism. Among their findings, microhabitat cover (0-1 m from a nest) is the most important habitat feature influencing the incidence of brood parasitism. Dense cover near nests likely reduces the ability of cowbirds to locate vireo nests and may shield parental activity from the view of searching cowbirds. Their findings, reported in the current issue of the Journal of Wildlife Management, provide data with which to design recovery strategies to minimize parasitism of least Bell’s vireo. For more: http://www.werc.usgs.gov/pubbriefs/kuspbaug2006.html. (Barbara Kus, San Diego, CA, 619-225-6421, barbara_kus@usgs.gov) Citation: Sharp, B. L. and B. E. Kus. 2006. Factors influencing the incidence of cowbird parasitism of least Bell’s vireos. Journal of Wildlife Management 70:682-690.

Invasive Weed Management Using Fire: A review article evaluating the current state of knowledge on prescribed burning as a tool for invasive weed management appears in a recent issue of the journal Weed Technology, and is coauthored by USGS scientist Matt Brooks of the Western Ecological Research Center and colleagues at University of California, Davis, California Department of Forestry and Fire Protection, and University of Montana, Missoula. The article provides a general overview of how fire can be used to manage invasive plant species; it gives several examples of approaches involving specific annual and perennial invasive species, and discusses integrated strategies and post-burn monitoring. For more: http://www.werc.usgs.gov/pubbriefs/brookspbaug2006.html. (Matt Brooks, Henderson, NV, 702-564-4615, matt_brooks@usgs.gov) Citation: DiTomaso, J. M., M. L. Brooks, E. B. Allen, R. Minnich, P. M. Rice, and G. B. Kyser. 2006. Control of invasive weeds with prescribed burning. Weed Technology 20:535–548.

Avian Monitoring at Camp Pendleton: USGS scientists Barbara Kus, Matt Dresser, Mike Wellik, and Jodie Falcone of the Western Ecological Research Center appear in an August 12, 2006, video news story produced by the Navy Marine Corps on wildlife stewardship at Marine Corps Base Camp Pendleton, California. USGS is participating in a long-term bird study at Camp Pendleton as part of the Monitoring Avian Productivity and Survival (MAPS) program in North America. To view the video news story: http://www.news.navy.mil/management/videodb/player/video.aspx?id=7638 . (Barbara Kus, San Diego, CA, 619-225-6421, barbara_kus@usgs.gov)

Biodiversity Hotspots Featured: USGS scientist Barbara Kus of the Western Ecological Research Center was interviewed about USGS research on endangered birds at Camp Pendleton as part of a feature film documentary by Dancing Star Foundation about critical habitats throughout the world and techniques that are working to save threatened, endangered and vulnerable species and genera. Camp Pendleton will be the focus of the southern California biodiversity hotspot, and in particular this segment will be presenting USGS research on least Bell's vireos. Other featured species will be California least terns, California gnatcatchers, and Pacific pocket mice. (Barbara Kus, San Diego, CA, 619-225-6421, barbara_kus@usgs.gov)

Desert Wildfires: USGS scientist Todd Esque of the Western Ecological Research Center was interviewed for an August 21 story in the Los Angeles Times about the role of invasive grasses in fueling desert wildfires and the threat to desert biodiversity. (Todd Esque, Henderson, NV, 702-564-4506, todd_esque@usgs.gov)

Too Few Studies Assess Success of Desert Tortoise Recovery Actions: Numerous scientific investigations have been undertaken with the purpose of advancing the recovery of the desert tortoise. However, a new USGS report finds that few of these studies specifically evaluate the effectiveness of management actions taken for the recovery of this federally threatened species and that more scientifically-based follow-up monitoring of actions needs to be implemented. The study, by USGS scientist emeritus William I. Boarman and William B. Kristan of the California State University, San Marcos, was commissioned by the Desert Managers Group (DMG). Their full report, USGS Scientific Investigations Report 2006-5143, “Evaluation of Evidence Supporting the Effectiveness of Desert Tortoise Recovery Actions,” is available at: http://pubs.usgs.gov/sir/2006/5143/index.html. (Bill Boarman, Spring Valley, CA, 619-861-9450, conservation-science@cox.net)

Zoo Exhibit Shows Research Techniques Biologists Use: Research techniques that biologists use to study animals, such as genetic testing, remote photography, and GPS tracking, will be highlighted as part of a new interpretive exhibit on the Amazon Basin at the Santa Ana Zoo in California. Helping to illustrate techniques researchers use are some examples on one of the exhibit displays drawn from research in southern California by USGS scientists at the Western Ecological Research Center: remote photography of mountain lions at night, mapping from wildlife tracking projects, and photographs show USGS scientist Dustin Wood doing lab work for a genetics study. The exhibit will be called the Bauer Jaguar Exploration Outpost and is expected to open August 26. This is the zoo’s second interpretive exhibit this year that has incorporated USGS research. For more: http://www.santaanazoo.org/. (Robert Fisher, San Diego, CA, 619-225-6422, rfisher@usgs.gov)

Desert Tortoise: USGS scientist emeritus William I. Boarman was interviewed August 10 by the Palm Springs Desert Sun regarding a new USGS report that evaluated the state of knowledge about the effectiveness of desert tortoise recovery actions. (Bill Boarman, Spring Valley, CA, 619-861-9450, conservation-science@cox.net)

Managing in the Face of Uncertainty: USGS scientist Nate Stephenson of the Western Ecological Research Center was interviewed August 8 for an article to appear in the summer 2006 issue of California Coast & Ocean magazine. Stephenson discussed approaches to managing ecosystems in the face of rapid environmental changes, including climatic change. (Nate Stephenson, Three Rivers, CA, 559-565-3176, nstephenson@usgs.gov)

Coping with Flammable Forests: USGS scientist Nate Stephenson of the Western Ecological Research Center was interviewed August 10 by the Los Angeles Times for an article on the tradeoffs between the two primary tools for reducing wildfire hazard in forests: prescribed fire and mechanical forest thinning. (Nate Stephenson, Three Rivers, CA, 559-565-3176, nstephenson@usgs.gov)

Shorebird Sampling in California for H5N1 Avian Influenza: USGS biologist Sam Iverson of the Western Ecological Research Center was interviewed about early detection surveillance sampling of shorebirds for H5N1 avian influenza in the San Francisco Bay for an August 10, 2006, story in USA Today. A reporter and photographer accompanied the USGS field crew to salt ponds in the South Bay, where the crew collected 48 samples for the day. This work is part of the early detection program funded through the U.S. Fish and Wildlife Service Region 1 and coordinated by the State of California, conducted cooperatively with PRBO Conservation Science and the Wildlife Health Center of the University of California, Davis. http://www.usatoday.com/news/health/2006-08-09-bird-flu-california_x.htm. (Sam Iverson, Vallejo, CA, (Sam Iverson, Vallejo, CA, 707-562-3003, saiverson@usgs.gov)

Parasite: USGS scientist Kevin Lafferty of the Western Ecological Research Center was interviewed for an August 9, 2006, story on ABCNews.com about possible effects of the common brain parasite Toxoplasma gondii on human cultural traits. http://abcnews.go.com/Technology/DyeHard/story?id=2288095&page=1 (Kevin Lafferty, Santa Barbara, CA, 805-893-8778, klafferty@usgs.gov)

USGS to Participate in Northern Pintail Meetings: The Pintail Action Group (PAG, http://www.siu.edu/~wildlife/PAG/Index.asp), an international group of public and private interests that bring researchers and managers together to address declines in northern pintail populations has organized an evening pintail workshop and day-long annual meeting to coincide with the 4th North American Duck Symposium in Bismarck, North Dakota, August 23-26, 2006 (www.4nads.com). USGS scientists will be participating, and current PAG Chair, USGS scientist Joe Fleskes of the Western Ecological Research Center, will lead both the pintail workshop and PAG annual meeting. Fleskes will also be giving a presentation on pintail winter ecology, co-authored by USGS scientist Mike Miller and others, and both scientists are co-authors on a talk on pintail spring ecology. The objective of the workshop is to discuss current knowledge, key uncertainties and adaptive management approaches to test hypotheses regarding ecology of northern pintails with the goal of improving management and conservation of the species. (Joe Fleskes, Dixon, CA, 707-678-0682 ext 628, joe_fleskes@usgs.gov)

Cat Parasite May Affect Cultural Traits in Human Populations: In a study published in the August 2, 2006 issue of the Proceedings of the Royal Society, Biology, USGS scientist Kevin Lafferty of the Western Ecological Research Center explored whether a behavioral manipulation of a common brain parasite, Toxoplasma gondii, might cause a shift in the average, or aggregate, personality of populations where the parasite has infected a higher proportion of individuals. The geographic variation in the latent prevalence of Toxoplasma gondii may explain a substantial proportion of human population differences in cultural aspects that relate to ego, money, material possessions, work and rules. Infection with Toxoplasma varies considerably from one population to another; in some countries it is very rare while in others nearly all adults are infected. In populations where this parasite is very common, mass personality modification could result in cultural change. (Kevin Lafferty, Santa Barbara, CA, 805-893-8778, klafferty@usgs.gov)

Invasive Ant Research: Presentations on factors influencing Argentine ant occurrence, coauthored by USGS and the University of California, San Diego, were presented by UCSD at the International Union for the Study of Social Insects (poster presentation) in Washington D.C. (July 30-Aug. 4, 2006) and at the Ecological Society of America (oral presentation) meeting in Memphis (Aug. 6-11, 2006) For more: http://www.iussi.org/IUSSI2006.html and http://www.esa.org/memphis/. (Robert Fisher, San Diego, CA, 619-225-6422, rfisher@usgs.gov)

Parasite: USGS scientist Kevin Lafferty of the Western Ecological Research Center was interviewed by newspapers, radio and web regarding his recent study in the Proceedings of the Royal Society, Biology on possible effects on cultural traits by the brain parasite Toxoplasma gondii. News coverage has included: Daily Telegraph, London (Aug. 2), BBC World Today (Aug. 2), CKNW AM in Vancouver, B.C. (Aug. 3), Contra Costa Times, CA (Aug 4.), LiveScience.com (Aug. 4) Fox News.com (Aug. 4) and others. (Kevin Lafferty, Santa Barbara, CA, 805-893-8778, klafferty@usgs.gov)

Santa Ana River Fish Sampling: In an August 7, 2006, Orange County Register story on USGS WRD NAWQA sampling in the Santa Ana River in southern California, BRD scientist Robert Fisher was interviewed about external parasites that he had found on fish sampled in late 1980s in the Santa Ana River, when significant dairy waste but less treated sewage flowed through the river. Now more treated sewage effluent flows through the river and few external parasites are found on fish, possibly due to increases in antibiotics in the water; biologists worry about potentially harmful effects of antibiotics and other compounds on the health of the stream. (Robert Fisher, San Diego, CA, 619-225-6422, rfisher@usgs.gov)