WERC Highlights -- April 2004

DWF Best Student Paper of the Year Award: USGS scientist Josh Ackerman of the Western Ecological Research Center recently won the award for the Best Student Paper of 2002 from the Delta Waterfowl Foundation for his publication "Of mice and mallards: positive indirect effects of coexisting prey on waterfowl nest success" in Oikos 99(3):469-480. Josh's research will be featured in an upcoming issue of the Delta Waterfowl magazine. (Josh Ackerman, Davis, CA, 530-754-4148, jackerman@usgs.gov)

Sea Otter Deaths: USGS scientist Brian Hatfield of the Western Ecological Research Center was interviewed for a story to run on April 15 in The Cambrian on a recent rise in sea otter deaths in San Luis Obispo County reported by California Department of Fish and Game,. Twenty live or dead-stranded sea otters have been recovered from a region centered near Morro Bay since April 4, 2004. (Brian Hatfield, San Simeon, CA, 805-927-3893, brian_hatfield@usgs.gov)

Mediterranean-climate Ecosystems Meetings: USGS scientist Jon Keeley of the Western Ecological Research Center will give a paper on “Invasive Plants and Fire Management in California Mediterranean-climate Ecosystems” at MEDECOS 2004, the 10th International Conference devoted to the world’s Mediterranean-climate ecosystems and organized by the International Society of Mediterranean Ecologists, to be held April 25-May 1, 2004 on Rhodes Island, Greece. MEDECOS brings together scientists working on various aspects of Mediterranean environments, to encourage presentations of latest advances in research and applications, to promote discussions, and to increase interactions among researchers and between researchers and managers. For more information: http://www.biology.uoa.gr/medecos/. Keeley will also speak on the “Evolution of Smoke-stimulated Germination” at the International Meeting on Seeds and the Environment, also to be held on Rhodes, on April 29-May 4. For more information: http://www.biology.uoa.gr/SeedEcology2004.htm/. (Jon Keeley, Three Rivers, CA, 559-565-3170, jon_keeley@usgs.gov)

Marine Disease: Infectious disease outbreaks have increased in natural communities in several major groups of marine life during the past 30 years, suggests a new review of scientific literature by Cornell University and the U.S. Geological Survey (USGS), published in the April issue of the Public Library of Science: Biology. In the absence of baseline data on changes in disease over time, this new study used publication effort by marine scientists as an indirect way to detect important trends of disease. USGS scientist Kevin Lafferty of the Western Ecological Research Center and Cornell University graduate student Jessica Ward found increased reports in scientific literature of disease outbreaks for turtles, corals (non-infectious bleaching), mollusks, mammals and urchins. The scientists detected no significant trends for seagrasses, decapods, corals (infectious disease) and sharks/rays, and, most surprisingly, they found evidence of decreased reports of disease outbreaks in fishes. With rising human stresses placed on the environment, understanding disease dynamics is vital to conserving marine ecosystems. Citation: Ward JR, Lafferty KD (2004) The elusive baseline of marine disease: Are diseases in ocean ecosystems increasing? PLoS Biol 2(4):e120 DOI: 10.1371/journal.pbio.0020120. (Kevin Lafferty, Santa Barbara, CA, 805-893-8778, klafferty@usgs.gov)

Merced River Restoration: USGS research geologist Mary Ann Madej of the Western Ecological Research Center has been invited by the National Park Service to review plans for Merced River restoration projects in Yosemite National Park. She will investigate the potential restoration sites in the field on April 20 and 21, and will discuss management implications of her channel monitoring study on the Merced River. (Mary Ann Madej, Arcata, CA, 707-825-5148, mary_ann_madej@usgs.gov)

Fire Ecology Workshop: USGS scientist Jon Keeley of the Western Ecological Research Center is one of three invited speakers for the San Diego Fire Recovery Network workshop to be held on April 21 at the San Diego Natural History Museum in Balboa Park. The free workshop, cosponsored by the San Diego Natural History Museum and The Nature Conservancy is for scientists, land managers, and others interested in fire ecology and vegetation management. The presentations will review what is known about managing vegetation in San Diego County to both minimize risks to life and property and sustain ecosystem health, how chaparral and coastal sage scrub vegetation structure affect fire behavior, and how fire history affects ecosystem healthy. A field trip on April 24 will visit sites along the chaparral-wildland interface. For more information contact: Mary Ann Hawke mhawke@sdnhm.org, phone 619-255-0301. (Jon Keeley, Three Rivers, CA, 559-565-3170, jon_keeley@usgs.gov)

Mercury and Migratory Birds in San Francisco Bay: A recently funded CALFED project is a collaborative effort by the U.S. Fish and Wildlife Service (Environmental Contaminants Division) and the U.S. Geological Survey (Western Ecological Research Center and Patuxent Wildlife Research Center) to use an integrated field and laboratory approach to evaluate the risks of mercury exposure to migratory birds in San Francisco Bay. Studies to begin this fall will examine the fate and effects of mercury at both north and south San Francisco Bay and encompasses fish-eating terns, diving ducks, and shorebirds and their habitats that range from the shallow subtidal to sloughs, wetlands, and salt ponds. Teams of scientists, technicians, and students will conduct field studies of avian movement, productivity, prey, and diet, and laboratory studies of mercury body burdens, isotopes, and genetics, as well as sensitivity studies of avian embryos to methylmercury. These studies are necessary to devise and prioritize mercury control strategies protective of Bay-Delta avian species. In addition to these biological studies, other USGS scientists are or will be conducting complimentary studies of physical and hydrological parameters that influence the fate of mercury and subsequent impacts on migratory birds. (Steve Schwarzbach, Sacramento, CA, 916-379-3745, steven_schwarzbach@usgs.gov; John Takekawa, Vallejo, CA, 707-562-2000, john_takekawa@usgs.gov; Keith Miles, Davis, CA, 530-752-5365, keith_miles@usgs.gov)

Black-crowned Night-herons of Alcatraz: Since 1990, USGS scientists, working closely with National Park Service biologists, have documented the temporal changes in nesting chronology, habitat use, colony use, hatching, and fledging success for black-crowned night-herons. Despite reduced numbers of nests in recent years, the Alcatraz Island heronry has been one of the most important sites for black-crowned night-herons in North San Francisco Bay, comprising an average of about one-third of the North-Bay population over the past 10 years. Black-crowned night-herons have nested on Alcatraz Island since at least the early 1980s. Their reproductive success on the island over the last 13 years is summarized in a study, which appears in the March issue of Waterbirds. The scientists found that the total number of nests per year reached a peak of 341 in 1996, falling to a low of 68 in 2001, and that contaminants appeared not to have significantly affected night-heron reproduction at Alcatraz. They found that other factors have likely affected reproduction on the island including: predation, especially by common ravens and Western gulls; interspecific competition with the Western gull, which has increased in numbers during the study period; habitat deterioration; and human disturbance. For more information: http://www.werc.usgs.gov/pubbriefs/hothempbapr2004.html. Citation: Hothem, R. L., and D. Hatch. 2004. Reproductive success of the Black-crowned Night Heron at Alcatraz Island, San Francisco Bay, California, 1990–2002. Waterbirds 27:112–125. (Roger Hothem, Dixon, CA, 707-678-0682 x626, roger_hothem@usgs.gov)

Postfire Wheat Seeding: A recent USGS study published in the International Journal of Wildland Fire illustrates the need for post-treatment monitoring of Burned Area Emergency Rehabilitation (BAER) projects, not only to determine effectiveness of treatment at attaining the desired goals of slope stabilization and reduced soil erosion, but to also evaluate negative ecosystem impacts. USGS scientist Jon Keeley of the Western Ecological Research Center investigated the ecological impacts of wheat seeding following a 2001 fire in mixed ponderosa pine-oak-chaparral in the newly created Giant Sequoia National Monument and the adjacent Sequoia National Forest in California. Comparing seeded and unseeded sites in the first postfire growing season, Keeley found that wheat was the dominant species on the seeded sites (67 percent of total cover) and disrupted the natural ecological structure of the plant communities. Seeded sites had 30-40 percent fewer species than unseeded sites. Species most strongly inhibited were postfire endemics whose life cycle is restricted to immediate postfire environments. Wheat seeding was also associated with an order of magnitude drop in ponderosa pine seedling recruitment, and coupled with remaining thatch, may inhibit pine recruitment in subsequent years. One goal of the BAER seeding project was to reduce alien species and Keeley showed that although other alien species were greatly reduced by wheat, he cautioned that this may not have a lasting effect because of the ecological vacuum caused by the demise of the non-persistent wheat. A summary is available at: http://www.werc.usgs.gov/pubbriefs/keeleypbapr2004.html. Citation: Keeley, J. E. 2003. Ecological impacts of wheat seeding after a Sierra Nevada wildfire. International Journal of Wildland Fire 13:73–78. (Jon Keeley, Three Rivers, CA, 559-565-3170, jon_keeley@usgs.gov)

Biology of Longevity: USGS scientist Nate Stephenson of the Western Ecological Research Center was interviewed by BBC for its upcoming two-part radio series called "Lifespans," which explores the biology of longevity. In particular, Stephenson discussed factors that allow giant sequoias to live more than 3,000 years. (Nate Stephenson, Three Rivers, CA, 559-565-3176, nstephenson@usgs.gov)

Shrubland Fires: USGS scientist Jon Keeley of the Western Ecological Research Center was interviewed by the Los Angeles Times for an upcoming story on California shrubland fires, in particular about a recent study by Keeley and colleagues that found there was generally not a strong relationship between fuel age and fire probabilities. Keeley was also interviewed by a freelance writer for a postfire piece in California Wild magazine. (Jon Keeley, Three Rivers, CA, 559-565-3170, jon_keeley@usgs.gov)