WERC Highlights -- August 2002

Largest Sea Otter on Record: USGS biologist Brian Hatfield of the Western Ecological Research Center recently captured the largest sea otter ever recorded, in the vicinity of Destruction Island off the outer coast of Washington. The adult male sea otter weighed 50.5 kilograms (111.6 pounds) and measured 151 centimeters (59.4 inches) in length. The otter handily surpassed the previous record of 46.2 kilograms and 149 centimeters, also a Washington otter, captured in 1997. Hatfield, a scientist with the USGS California Sea Otter project team based in Santa Cruz, captured the sea otter from underneath while the otter was resting in kelp. Specialized capture equipment includes basket-like traps attached to the front of underwater scooters and closed-circuit oxygen rebreathers (to enhance the divers’ stealthly approach). Hatfield caught the otter as part of a project to monitor contaminant levels in Washington sea otters, sponsored by the U.S. Fish and Wildlife Service. In addition to USGS, other cooperators in this study include the Olympic Coast National Marine Sanctuary and the Washington Department of Fish and Wildlife. (Brian Hatfield, San Simeon, CA, 805-927-3893)

Exotic Frog Invaders: On Aug. 28, T’Shaka Toure and Sara Compton, USGS biologists at the Western Ecological Research Center, led Irvine city officials and a National Geographic team on a 4-hour trip to look for African clawed frogs, an exotic species infesting ponds in Irvine, California. During the outing, the biologists captured clawed frogs for the group to view, and Toure, the lead scientist for a project designed to eradicate this exotic frog in Irvine, discussed the frog’s natural biology and behavior. National Geographic scouted locations to film a TV documentary on people and frog phobias and conservation issues regarding the exotic African clawed frog. Introduced to the United States in the 1960s, the African clawed frog feeds on native frog tadpoles and can travel overland by night during rainy periods, invading new locales. Its name refers to the sharp, black claws on the inner toes of its webbed hindfeet. A photo and information about the African clawed frog are at: http://www.werc.usgs.gov/fieldguide/xela.htm. (T’Shaka Toure, Irvine, CA, 714-330-5042)

Washington Sea Otters: Brian Hatfield, a USGS biologist at the Western Ecological Research Center, was interviewed and photographed for a story in the Tacoma News Tribune, for a nature feature about sea otters. Hatfield was capturing sea otters as part of a study to monitor contaminant levels in Washington otters. The story is expected in early September. (Brian Hatfield, San Simeon, CA, 805-927-3893)

Scientists Find More Frogs along Creek: Robert N. Fisher, a USGS research zoologist at the Western Ecological Research Center, was interviewed by the Los Angeles Times and Los Angeles Daily News about recent red-legged frog surveys that indicate there are more frogs along the San Francisquito Creek in the Angeles National Forest of southern California than previously thought. Before the June Copper Fire, scientists had estimated only about 50 of the threatened red-legged frogs lived in creekbed pools. The fire cleared underbrush, however, giving biologists greater access to frog habitat. They captured and implanted microchips under the skin of about 85 frogs, seeing but not catching about 50 more. The clearing of underbrush has made the frogs more visible to predators, however, as well as frog biologists. These stories also ran in additional California newspapers. (Robert N. Fisher, San Diego, CA, 858-637-6882)

Temperature Variations in Mojave Desert fires Can Alter Annual Plant Communities: In a recent article in the journal Ecological Applications, USGS research botanist Matt Brooks of the Western Ecological Research Center reports that significant variation in fire temperatures among three desert microhabitats can result in variable annual plant responses in the years following a fire. Fire had variable effects on alien plants, reducing abundance of one species and increasing abundance of two others. Fire temperatures were highest beneath the creosote bush canopy, intermediate beneath the edge of the canopy, and lowest in the interspace between shrubs. Annual plant community responses differed among these microhabitats due to small-scale variation in fire temperatures, microhabitat preferences of the species, and the species composition of the seedlings and their stages of development at the time of burning. The results indicate that fire effects models for the Mojave Desert must account for fire temperatures and effects on annual plants along the shrub-intershrub gradient. A non-technical summary of these research findings is available in a downloadable publication brief at http://www.werc.usgs.gov/pubbriefs/. (Matt Brooks, Henderson, NV, 702-564-4615)

Wildlife Corridors: USGS scientists at the Western Ecological Research Center were interviewed for a Discover Magazine story describing how scientists use methods such as camera surveys and track stations to document wildlife movements between blocks of habitat in southern California that are separated by highways and other urban development. Photos of a coyote, mountain lion, and fox taken by motion-triggered cameras in USGS surveys were included in the story in the current September issue of the magazine. (Robert N. Fisher, San Diego, CA, 858-637-6882)

Western Fires: USGS fire ecologists Jan van Wagtendonk and Jon Keeley of the Western Ecological Research Center were interviewed for stories on wildfires: van Wagendonk by the New York Times about reducing the threat of catastrophic fire in forests; Keeley by the Contra Costa Times about large wildfires that occur in California chaparral shrublands. (Jan van Wagtendonk, El Portal, CA, 209-379-1306; Jon Keeley, Three Rivers, CA, 559-565-3170)

Giant Sequoias: USGS scientist Nate Stephenson was filmed for an upcoming installment of "The Grand View," a public television series featuring America's national parks. Stephenson spoke about the history and ecology of giant sequoias, and threats to California's Sierra Nevada mountain range, such as air pollution, altered fire regimes, and rapid climatic change. The segment is scheduled to air in November or December. (Nate Stephenson, Three Rivers, CA, 559-565-3176)

Urban Coyotes: USGS research ecologist Erin Boydston of the Western Ecological Research Center was interviewed by the Marin Independent Journal for a story in the Sunday issue about increased sightings of coyotes in urban areas of Marin County. (Erin Boydston, Sausalito, CA, 415-331-0639)

Waterfowl Studies: The Aug.-Sept. issue of California Waterfowl, the magazine of the California Waterfowl Association (CWA), featured a story on waterfowl research by USGS scientists at the Western Ecological Research Center. The scientists are using satellite and VHF radiotags to document spring migration patterns and habitat use of northern pintails that winter in California's Central Valley. USGS research wildlife biologist Joe Fleskes was quoted in another story in the same magazine issue on the importance of CWA's mallard research program. (Joe Fleskes, Dixon, CA, 707-678-0682 x628)

Research for Maintaining Wildlife Corridors: Wildlife corridors link blocks of habitat used by native species in southern California, a region of rapid urban growth. USGS scientists at the Western Ecological Research Center in San Diego provide science expertise for California’s South Coast Missing Linkages Project to assess the use of existing corridors by native species and better understand their corridor needs. Ensuring the viabilitiy of landscape linkages for all native species of the region is the goal of the South Coast Missing Linkages Project. USGS scientists Robert Fisher and Chris Brown were invited speakers at recent Missing Linkages workshops, where they presented results of ichthyological and herpetological research of southern California mountains. (Chris Brown, San Diego, CA, 858-637-6883)

Emergency Efforts to Save Endangered Frogs: USGS scientists at the Western Ecological Research Center in San Diego have been working with U.S. Fish and Wildlife Service, U.S. Forest Service, San Diego Zoo, and California Department of Fish and Game in a race against drought conditions to develop a strategy to save mountain yellow-legged frog larvae (Rana muscosa) from drying creeks in southern California mountains. The plan includes relocating second-year frog larvae from pools at risk of drying, to nearby pools having sufficient water for the larvae to complete metamorphosis into adult frogs over the next few weeks. First-year larvae, smaller and in greater jeopardy of dessication, will be moved to the San Diego Zoo, where they will remain under quarantine for release when mountain streams again have adequate water to sustain them. Considered one of the rarest amphibians in the nation, the mountain yellow-legged frog in southern California was added to the Endangered Species list August 1, 2002. The final rule on this frog in the Federal Register relied heavily on research conducted by USGS biologists in San Diego, citing technical reports for the U.S. Forest Service produced by USGS scientists. (Chris Brown, San Diego, CA, 858-637-6883)

Taiwanese Biodiversity Symposium: USGS research biologist Gary Fellers of the Western Ecological Research Center will be traveling to Taiwan Sept. 2-12 as part of a group of five USGS scientists who have been invited to participate in a "Symposium on Biodiversity Research." The group will visit several Taiwanese national parks and will be meeting with various government officials and university representatives. Fellers will be giving lectures on amphibian declines and exploring opportunities for collaboration with Taiwanese colleagues. (Gary Fellers, Pt. Reyes, CA, 415-464-5185)

Fire Fans Media Interest at ESA Conference: The Arizona Daily Star and Tucson Citizen reported on a panel discussion about the recent Arizona wildfires led by five fire ecologists, including USGS scientists Jon Keeley and Craig Allen. Matt Brooks, also a USGS fire ecologist, was interviewed about fire and invasive species interactions for the noon and evening news on KVOA-TV, the Tucson NBC affiliate, and for an upcoming story in the Toronto Sun. (Gloria Maender, Tucson, AZ, 520-670-5596)

Wintering Northern Pintails in California: Despite loss of over 90 percent of California’s Central Valley wetlands since the early 20th century, about half of the pintails in North America still winter there, arriving as early as the first week of August and remaining through March. Why are they less abundant in the San Joaquin Valley than other central California areas? Are they dying from diseases and contaminants? To answer these questions, USGS scientists Joe Fleskes and Dave Gilmer of the Western Ecological Research Center and Oregon State University professor Robert Jarvis radiotagged a total of 419 young and adult female pintails in the San Joaquin Valley in late summer 1991, and tracked their survival in central California until spring each year for three years. They found that hunting accounted for 83 percent of deaths in the radiotagged pintails, and young pintails were more vulnerable than adults to hunting pressure. Drought, habitat conditions, agricultural crop type, and flooding of fields were also factors in pintail survival. The study provides a better understanding of winter survival needed to project pintail recruitment and harvest. Results of this study are reported in a recent issue of the Journal of Wildlife Management. For management implications, please visit the WERC publication brief titled “September-March Survival of Female Northern Pintails Radiotagged in San Joaquin Valley, California” at http://www.werc.usgs.gov/pubbriefs/. (Joe Fleskes, Dixon, CA, 707-678-0682 x628)

How Humans have Affected Natural Fire Regimes: USGS research ecologist Jon Keeley of the Western Ecological Research Center will speak on the "Human Impact on Fire Regimes" on Tues., Aug. 13, at the "Disturbance Dynamics in Boreal Forests" conference, to be held at the University of Northern British Columbia in Port George, Canada. Information about the conference is available at http://www.res.unbc.ca/borealdisturbance/. (Jon Keeley, Three Rivers, CA, 559-565-3170)