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Predicting the Consequences of Wave Energy Absorption from Marine Renewable Energy Facilities on Nearshore Ecosystems Wave energy conversion (WEC) devices extract potential energy from the rise and fall or surge of o ...more
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Identifying Kittlitz’s Murrelet nesting habitat in North AmericaThe Kittlitz’s Murrelet is a small, non-colonial seabird endemic to marine waters of Alaska and east ...more
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Research and Restoration in the California Channel IslandsChannel Islands habitats off California is ecologically important and extremely vulnerable to distur ...more

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A Field Guide to the Reptiles and Amphibians of Coastal Southern CaliforniaField Guide Developed By:  Robert Fisher and Ted J. Case with photos by Chris Brown 
A Nevada State Map of Greater Sage-Grouse HabitatCan USGS science help BLM and state agencies discover management options that balance habitat conser ...more
A Test of Inventory and Monitoring Techniques for Terrestrial Amphibians, Reptiles, Small Mammals, and CarnivoresA wide variety of methods have been employed for the inventory and monitoring of terrestrial amphibi ...more
Aleutian Islands Contaminant Monitoring ProgramElevated PCB levels occur at Adak Island, Alaska. The source and chronology of these environmental c ...more
Alpine Mammals in Meadows of the Sierra Nevada We are proposing to model: (1) range shifts for five alpine mammal species and, (2) the degree to ...more
American Badgers in San Diego CountyCitizen scientists can now help dig into San Diego's urban wildlife mysteries. Join WERC ecologists ...more
Amphibian Research Monitoring Inventory DatabaseAmphibian population declines have been observed in many areas around the world.  Initially, th ...more
Animal Space Use in 2D and 3DTo create better maps and visualizations of wildlife movements, USGS researchers are looking into th ...more
Annual movements of Pacific Flyway Lesser Sandhill Cranes summering near Homer, AlaskaThis project will document local movements of cranes during early and late summer periods, and docum ...more
Archiving California’s Breeding Duck DataThe U.S. Geological Survey, California Waterfowl Association, University of California-Davis, and Ca ...more
ARMI Population Status and MonitoringApproximately 230 species of frogs, toads, and salamanders make up the amphibian fauna of the contin ...more
Bat Research in CaliforniaThe contact for the San Diego county area is Drew Stokes (, the contact for the San ...more
Bear Creek Mercury Monitoring ProtocolThe Bureau of Land Management (BLM) must demonstrate that it manages public lands under its administ ...more
Bird Use of Restored Riparian HabitatRiparian habitat in the southwestern United States has undergone serious declines during the last se ...more
Breeding Waterbird Ecology and ManagementFor most avian taxa, the breeding season from spring nest initation to fall fledging is the most imp ...more
Brushfires in California: Ecology and Resource ManagementIn light of the recent southern California fires there have been requests for information relating t ...more
California Current Ecosystem Seabird Telemetry Atlas (CCESTA)WERC scientists and partners are creating an atlas of seabird distribution and movement data across ...more
California Gull Population Growth and Predation on Breeding Waterbirds The California Gull population in San Francisco Bay has increased from <200 in 1982 to > ...more
California Sea Otter Stranding NetworkThe California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters ...more
California Sea Otter Surveys and ResearchWERC scientists conduct annual population surveys of the southern sea otter -- a federally listed th ...more
Carbon budgets and geomorphic processesThe development of carbon markets as one tool to reduce greenhouse gases and their role in global cl ...more
Central Valley Waterfowl Changing agricultural practices and conservation programs such as the Central Valley Joint Venture ( ...more
Changing Landscapes of Santa Rosa IslandHave the ecosystems of the Channel Islands changed over the decades? An effort to match archival pho ...more
Channel Islands Rare Plants SurveyThe least-visited National Park in the United States is also home to an astounding diversity of ende ...more
Chipmunk Competition in the Sky Islands of NevadaHow will climate change alter the food web of the "sky islands" of the Basin and Range Pro ...more
Climate and Fire in the Sierra NevadaMountain ecosystems, with their geographic compression of climatic gradients and biological communit ...more
Coastal Ecosystem Response to Sea-Level Rise Coastal marshes and estuaries are currently being reshaped by changing ocean and atmospheric condi ...more
Common Murre associations with the Columbia River Plume and adjacent watersThe murre (pronounced “mrr-rr-rrr,” in imitation of the bird’s vocalizations) is a football-sized se ...more
Conservation genetics of the endangered Alameda whipsnakeThe Alameda whipsnake (Masticophis lateralis euryxanthus) is both a federally and state listed endan ...more
Contaminant Immune FunctionsThere are multiple facets to Contaminant Immune Function studies at the WERC Davis Field Station, tw ...more
Contaminant Studies on Mercury and SeleniumStudies supported by this task include investigation of mercury in sediments and biota at the San Fr ...more
Contaminants in Waterbirds and Effects on Avian ReproductionCalifornia’s Central Valley and San Francisco Bay Estuary have a long history of mercury contaminati ...more
Contaminants in Waterbirds Breeding in the Great Basin The Great Salt Lake ecosystem, located in northern Utah within the Great Basin, has been designate ...more
Demography of the Joshua Tree, a Long-Lived Arborescent Yucca, Across Five Mojave Desert National ParksThe Mojave Desert is the hottest and driest among the North American deserts, but in spite of these ...more
Desert Bighorn Sheep at the Wildland-Urban InterfaceDesert bighorn sheep populations are dependent on rainfall patterns, and must further adapt to clima ...more
Desert Bighorn Sheep in Joshua Tree National ParkProtected lands managers must sometimes balance wildlife resource needs with human recreation goals. ...more
Desert Tortoise Hibernation: Temperatures, Timing, and EnvironmentThe federally listed Mojave population of the desert tortoise receives much attention from scientist ...more
Desert tortoise research and monitoring on Federal and State lands in CaliforniaThe desert tortoise, Gopherus agassizii, was listed by the state and federal governments as a threat ...more
Designing a Tricolored Blackbird SurveyTri-colored blackbirds are nearly endemic to California, and this species is listed on the U.S. Fish ...more
Development of Native Plant Materials for Rehabilitation of Disturbed Mojave Desert ShrublandsRecent large-scale fires driven by exotic annual grass species have increased the need for shrubland ...more
Discovery For Recovery: An International Pintail Recovery InitiativeA team of waterfowl biologists with the U.S. Geological Survey's Western Ecological Research Center, ...more
Ecology and Conservation of Wild Birds in the Poyang Lake Region: a Satellite Telemetry Pilot ProjectAn international team from U. S. Geological Survey (Western Ecological Research Center, Patuxent Wil ...more
Ecology and Habitats of Central Valley Waterfowl and other Waterbirds This project evaluates projected impacts of climate, urbanization, and water management scenarios ...more
Ecology of California Clapper Rails in the San Francisco Bay/Delta RegionThe California Clapper Rail (Rallus longirostris obsoletus) is a federal and state listed endangered ...more
Ecology of northern pintails and other waterfowl during spring in Southern Oregon - Northeastern California (SONEC).Southern Oregon-Northeastern California (SONEC) provides critical spring staging habitat for norther ...more
Ecology of Two Contrasting Endangered Endemic Dune Plants at Death Valley National Park, CaliforniaThe Eureka Dunes is an ecologically distinct environment that supports several endemic and endangere ...more
Ecosystem Carbon Sequestration and Restoration of Coastal Redwood ForestsForests contain the majority of terrestrial carbon and land management activities have the potential ...more
Effects of Pack Stock Grazing on Mountain Meadow EcosystemsUSGS Scientist Matt Brooks is  developing an annotated review of the literature pertaining to i ...more
Effects of Wildfires on Desert Tortoise HabitatsIn the deserts of the Southwestern United States, fire size and frequency have increased substantial ...more
Elkhorn Slough Sea Otter ResearchHow are sea otters using estuarine habitats and prey resources? Researchers are seeking to understan ...more
Endangered Hawaiian Seabirds Hawaiian seabird species are impacted by non-native predators and habitat degradation.  Studies of ...more
Evaluating Postfire Seeding Treatments Designed to Suppress Cheatgrass (Bromus tectorum) in a Ponderosa Pine Forest on the Colorado PlateauThe restoration of historical fuel conditions and fire regimes is one of the primary land management ...more
Evaluating the Effects of Pinyon Thinning Treatments at a Wildland Urban InterfaceThis study evaluated the short-term effects of thinning methods for pinyon pine woodlands at two sit ...more
Evaluation and refinement of conventional approaches for post-fire rehabilitation of desert tortoise Critical Habitat Recent wildfires burned an unprecedented 1 million acres of Mojave Desert shrublands in 2005/2006, ...more
Evaluation of Satellite Telemetry Techniques for Migration and Distribution of Band-Tailed PigeonsThe Pacific Coast band-tailed pigeon (Patagioenas fasciata monilis) winters mainly in southern Calif ...more
Experimental Treatments to Eradicate or Control Buffelgrass at Saguaro National ParkA number of invasive perennial and annual exotic grasses are identified as serious threats to native ...more
Fate of endangered species in San Francisco Bay tidal marshes with sea-level rise The San Francisco Bay estuary, though severely fragmented and modified, represents the largest ext ...more
Finding Evolutionary Hotspots in Southern California for Conservation PlanningThe mission of the California State Park system is "to provide for the health, inspiration and ...more
Fire Effects on Seedbanks and Vegetation in the Eastern Mojave Desert: Implications for Postfire ManagementLimited information is currently available on the short-term effects of fire on the soil seedbanks a ...more
Fire Science in the Sierra NevadaFire is both a critical natural ecosystem process, and at times a hazard to human life, infrastructu ...more
Fire Severity TrendsWe are testing the idea that climate may affect forest fire severity independent of fire intensity. ...more
Flightless and Post-molt Survival and Movements of Female Mallards Molting in Klamath Basin Flightless and post-molt survival and movements were studied during August–May, 2001–2002, 2002–2003 ...more
Foraging Ecology and Environmental Contaminants in Migratory Birds in the San Francisco Bay EcosystemSan Francisco Bay is one of the most important wintering and stopover sites for migratory birds on t ...more
Genetic Determination of source populations of the California red-legged frog for reestablishment efforts in southern California The once common California red-legged frog (Rana draytoni) previously described as a subspecies, R ...more
Giant Gartersnake StudiesCalifornia's Central Valley is home to the largest gartersnake species—Thamnophis gigas—which is als ...more
Greater Sage-Grouse ResearchThe Greater Sage-Grouse has been listed as a Candidate Species for consideration by the Endangered S ...more
Griffith Park Connectivity StudyWildlife must navigate the confusing maze of disconnected habitats and urban barriers that crisscros ...more
Historical record of Mercury in San Francisco Bay Tidal MarshesThe mercury content of SF Bay bottom sediments has been previously shown to be enriched 7 fold from ...more
Identifying Kittlitz’s Murrelet nesting habitat in North AmericaThe Kittlitz’s Murrelet is a small, non-colonial seabird endemic to marine waters of Alaska and east ...more
Impacts of Human Activity and Development on Behavior, Genetics, Disease and Mortality on Bobcats and other CarnivoresHabitat fragmentation is one of the principle threats to biodiversity, and in developing landscapes, ...more
Impacts of Pre-Fire Fuel Manipulation on Fire Behavior in Southern CaliforniaFire hazards are unlike other hazards such as earthquakes because there is the potential for managem ...more
Impacts of Pre-Fire Fuel Manipulation on Fire Behavior in Southern CaliforniaFire hazards are unlike other hazards such as earthquakes because there is the potential for managem ...more
Increasing Forest Resistance to Drought Using Prescribed FireUsing the current severe drought in the southwestern U.S. as a natural experiment, USGS scientists a ...more
Intraspecific Phylogeography of the Rosy Boa (Charina trivirgata): Implications for Phylogeography, Taxonomy, and ConservationThe Rosy boa (Lichanura trivirgata) is found throughout the semi-arid and arid regions of southweste ...more
Invasive weed removal and habitat restoration: Sahara mustard Sahara mustard (Brassica tournefortii) is one of the top non-native invasive plants of concern for l ...more
Island Night Lizard Population Ecology on the Channel Islands    The island night lizard (Xantusia riversiana) is a medium-sized lizard (adul ...more
Landscape Conservation CooperativesThe Landscape Conservation Cooperatives (LCC) form a network of public-private partnerships providin ...more
Long Term Monitoring and Management of the Endangered Arroyo Toad (Anaxyrus californicus) It is important that monitoring programs for endangered species provide valid scientific informati ...more
Long Term Monitoring and Management of the Stephens' kangaroo rat (Dipodomys stephensi) It is important that monitoring programs for endangered species provide valid scientific informati ...more
Long-term effects of prescribed fire on forest fuels across the western United StatesUsing long-term records from over 470 separate plots, we are test the idea that prescribed fire can ...more
Long-term monitoring program guidance and data analysis for Channel Islands National ParkRarely do agencies have the opportunity to research ecosystem change in undisturbed landscapes manag ...more
Main Hawaiian Islands Seabird Tracking StudyHawai'i provides substantial breeding habitats for more than a dozen bird species. WERC is providing ...more
Mapping habitat and genetic diversity in the desert southwest Multiple utility-scale solar, wind and geothermal energy development projects are currently underw ...more
Measuring Genetic Connectivity among Coastal Cactus Wren Populations in Southern California The coastal cactus wren is a fragmentation-sensitive resident passerine in southern California req ...more
Mercury Accumulation at the San Luis National Wildlife RefugeUnder the Clean Water Act, the Central Valley Regional Water Quality Control Board (CVRWQCB) has or ...more
Mercury Bioaccumulation in Wetlands Wetlands provide numerous ecosystem services, but also can be sources of methylmercury production ...more
Mercury Contamination and The South Bay Salt Pond Restoration ProjectThe San Francisco Bay Estuary has a long history of mercury contamination from past mercury and gold ...more
Mercury Contamination from Mining SourcesHistorical gold and mercury mining are major sources of mercury contamination in northern California ...more
Migration of Lesser Scaup Breeding in Montana:Routes and DestinationsThe continental population of scaup (Aythya affinis and A. marila) reached an all time low in 2006, ...more
Migration of Surf Scoters Along the Pacific Coast - Spring Migration 2006A large proportion of diving ducks in the Pacific Flyway are found in the San Francisco Bay estuary ...more
Migratory Linkages between Wintering and Breeding WaterfowlCalifornia hunters annually harvest more than 300,000 mallards, the third most among states in the U ...more
Modeling Sea-Level Rise in San Francisco Bay EstuaryWith climate change and sea level rise, how will the coastal habitats of the San Francisco Bay Estua ...more
Mojave Desert Science Symposium 1999Welcome to the home page for the Mojave Desert Science Symposium. This historic forum brought togeth ...more
Monitoring avian productivity and survival at Marine Corps Base Camp PendletonThe MAPS (Monitoring Avian Productivity and Survival) program is an international cooperative effort ...more
Monitoring Avian Productivity and Survival at Marine Corps Base Camp Pendleton, CaliforniaBackground and Justification: Protection and management of endangered birds is a primary focus of re ...more
Monitoring Mercury's Risk to Wildlife in California LakesUSGS scientists sampled grebes in California lakes to compare mercury levels in these predators vers ...more
Monitoring the Status of Declining Amphibians in California and Arizona: Compelling evidence from many areas around the world indicate that amphibians are declining on a glo ...more
Movements of Wild Birds and Emerging Disease Risk from Hong KongThe identification of breeding ranges of various waterfowl species congregating on wintering grounds ...more
Movements of Wild Birds and Emerging Disease Risk from India The study of the wintering (non-breeding) grounds for waterfowl allows identification of areas whe ...more
Nonnative Grass Invasions and Fire in the Mojave Desert Fires in the Mojave Desert appear to have been infrequent historically. When fires did occur, gaps o ...more
NRPP: How Rainfall and Temperature Affect Island Hydrology and Plant Resources The California Channel Islands support an incredible diversity of endemic plants and animals whose ...more
Pacific Coast Fisheries GIS Resource DatabasePacific Coast fisheries information is currently available only from wildlife agencies in disparate ...more
Pacific Continental Shelf Environmental Assessment (PaCSEA)The Pacific Continental Shelf Environmental Assessment (PaCSEA) is an aerial survey project of seabi ...more
Pacific Nearshore ProjectSea otters are crucial indicators of the health of our nearshore waters and coastal resources, from ...more
Pacific Pocket Mouse Monitoring Plan for MCB Camp Pendleton: Short Term Studies and Long Term GoalsPrepared by C.S. Brehme and R.N. Fisher, U.S. Geological Survey, Western Ecological Research Center ...more
Palmyra Atoll Research ConsortiumThe Palmyra Atoll Research Consortium (PARC) is a collaboration among government, academic and priva ...more
Persistence of sediment problems in salmon-bearing riversMany rivers in the United States have been disturbed by increases in sediment loads from activities ...more
Pesticide Impacts on Sierran Amphibians    Insecticides from the Central Valley of California are drifting into montane regions where amphi ...more
Phylogenetics of the Mahogany Jerusalem Cricket in Southern CaliforniaHabitat loss and fragmentation due to urbanization are the most pervasive threats to biodiversity in ...more
Phylogeography of the Coachwhip snake (Masticophis flagellum)The complex geological history of California has played a major role in shaping the evolutionary his ...more
Pintail habitat use and abundance during spring migration in the Klamath Basin and other Southern Oregon-northeastern California locations.Satellite tracking of pintails and surveys have identified the SONEC region as especially important ...more
Population Status and Conservation of the Rosy Boa (Lichanura trivirgata) The recent "explosive growth" of the international pet trade, with the United States in ...more
Population Structure and Demography of the Least Bell's Vireo and Southwestern Willow FlycatcherThe least Bells vireo (Vireo bellii extimus) and southwestern willow flycatcher (Empidonax traillii ...more
Post-fire Monitoring of Small Animal and Vegetation Communities in San Diego County In 2003 and 2007, large wildfires burned much of San Diego County, including hundreds of thousands ...more
Post-Fire Treatment Impacts on Fine Fuels in Westside Sierra Nevada ForestsTemporary link to old web site  This study, funded by the Joint Fire Science Program, invest ...more
Predicting the Consequences of Wave Energy Absorption from Marine Renewable Energy Facilities on Nearshore Ecosystems Wave energy conversion (WEC) devices extract potential energy from the rise and fall or surge of o ...more
Pre-Fire fuel manipulation impacts on alien plant invasion of wildlands  This project investigates the role of pre-fire fuel reduction manipulation projects in the invasi ...more
Range-wide genetic assessment of the federally endangered Riverside fairy shrimp, Streptocephalus woottoniThe Riverside fairy shrimp Streptocephalus woottoni is a federally endangered freshwater crustacean ...more
Rapid Genetic Identification of Southern California Fairy Shrimp Species from CystsIn southern California, the endangered San Diego fairy shrimp (Branchinecta sandiegonensis) and the ...more
Rapid Rice Availability Assessment MethodRice seeds obtained from harvested fields in the Sacramento Valley of California, and other rice gro ...more
Reproductive Success of Black-crowned Night-Herons and Snowy Egrets at Alcatraz Island, San Francisco Bay, CaliforniaStudies conducted in the early 1980s suggested that environmental contaminants adversely affected re ...more
Research and Restoration in the California Channel IslandsChannel Islands habitats off California is ecologically important and extremely vulnerable to distur ...more
Resistance and Resilience of Soil Seed Banks in Burned Mojave Desert Vegetation CommunitiesFew studies document changes in soil seed banks of desert species following wildfire, yet determinin ...more
San Francisco Bay Benthic Macroinvertebrate Atlas   Information on benthic macroinvertebrate population ...more
Seabird Vulnerability Assessment for Renewable Energy ProjectsProviding scientific data on seabird ecology to inform project design and siting for federal offshor ...more
Sierra Nevada Forest Dynamics: Studying Forest Health Forests provide humans with economically important and often irreplaceable ecosystem products and ...more
South Bay Salt Pond Restoration ProjectThe largest tidal wetland restoration project on the West Coast is unfolding at the edge of Silicon ...more
Southern California Wildfire Risk Scenario ProjectEvery year, wildfires devastate the landscapes of Southern California from Los Angeles to San Diego. ...more
Spatial Database for the At-Sea Distribution and Abundance of Seabirds and Marine Mammals off Southern California: 1999-2002From 1999-2002, the U.S. Geological Survey (USGS) and Humboldt State University (HSU) worked with th ...more
Spring Migration of Eurasian Wigeon from Northeastern California: Routes and DestinationsThe Eurasian Wigeon (Anas penelope) is a frequent winter visitor to the west coast of North America, ...more
Suisun Marsh Waterfowl and Waterbird StudiesSuisun Marsh is a critical habitat for wintering and breeding waterbirds in California. USGS is work ...more
Summary of Seabird Studies at WERC Seabird research by scientists at the San Francisco Bay Estuary Field Station of the USGS Western ...more
Taking the pulse of the forest: Klamath Network old-growth forest plotsOld-growth forests may appear timeless, but there are many recent examples showing how climate chang ...more
The Role of Pesticides in Amphibian DeclinesCompelling evidence from many areas around the world indicate that amphibians are declining on a glo ...more
Tidewater Goby Monitoring Program at Camp PendletonTidewater gobies are an endangered species that inhabits coastal lagoons.  Several populations on Ma ...more
Translocation of Desert Tortoises in Fort IrwinThe National Training Center (NTC) at Fort Irwin, California, provides the Army with essential train ...more
Use of Genetic Techniques to Evaluate the Impacts of Urbanization and Fragmentation on Wildlife, from Wide-ranging to Sedentary SpeciesUrbanization and fragmentation can have significant negative effects on wildlife communities includi ...more
Using Parasites to Monitor Ecosystem Health Although we tend to concentrate on the problems posed by infectious disease, parasites can play a po ...more
Vital Signs of Salmon Streams: North Coastal California National Park UnitsInvestigating the effects of abiotic drivers on aquatic habitats and salmon species. Part of the Nat ...more
Water Traffic and San Francisco Bay BirdsHow do waterbirds respond to the bustling recreational and transit water traffic of San Francisco Ba ...more
Waterbird Nesting Ecology in San Francisco BayThe San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually s ...more
Waterfowl Breeding EcologyPredators are the primary cause of duck nest failure and can significantly limit recruitment, potent ...more
Waterfowl Ecology and Population Dynamics We are investigating several aspects of waterfowl ecology, population trends, and population dyn ...more
Western Pond Turtle population genetic structure and diversity in southern CaliforniaThe western pond turtle (Emys marmorata (syn.  Actinemys marmorata) is the only freshwater turt ...more
Wild Bird Migratory Ecology, Emerging Disease Risk and Physiology in Western MongoliaTerkhiin Tsagaan Lake in west-central Mongolia is an important breeding and molting areas for Bar-he ...more
Wild Birds and Emerging Diseases: Avian Influenza transmission risk & the Migratory Ecology of African wild ducksVery little is known about the migration patterns of wild ducks in Africa or their possible involvem ...more
Wild Birds and Emerging Diseases: Avian Influenza transmission risk & wild birds in NigeriaHighly pathogenic avian influenza (HPAI) of the lethal subtype H5N1 was first detected in Nigeria in ...more
Wild Birds and Emerging Diseases: Avian Influenza Transmission Risk and Movements of Wild Birds from KazakhstanThe United States Geological Survey (USGS) has been working in partnership with the United Nations F ...more
Wild Birds and Emerging Diseases: Bangladesh: A source of Highly Pathogenic H5N1 infection in wild birds?Bangladesh attracts huge numbers of wild birds that overwinter in wetland habitat offered by the Gan ...more
Wild Birds and Emerging Diseases: Investigating the role of geese from Eastern Mongolia in the potential spread of avian influenza virus.The death of large waterfowl species such as wild swans (Cygnus spp.) has been one of the first indi ...more
Wild Birds and Emerging Diseases: Migratory birds and transmission of Highly Pathogenic H5N1 in TurkeyIn Turkey, highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype first emerged during 2 ...more
Wild Birds and Emerging Diseases: Modeling Avian Influenza Transmission Risk Between Domestic and Wild Birds in ChinaQinghai Lake National Nature Reserve is the largest saline lake in northwest China, and the site of ...more

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