Filters: Contacts: John Y Takekawa (X) > partyWithName: John Y Takekawa (X) > partyWithName: Western Ecological Research Center (X)
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San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and estuarine birds. Sources of mercury to the watershed since 1845 include sediment-associated mercury from mercury mining, mercury losses from gold amalgamation activities in mines of the Sierra Nevada, aerial deposition of mercury from global and regional emissions to air, and the direct discharge of mercury to Bay waters associated with the urbanization and industrialization of the estuary. We assessed historical trends in mercury bioaccumulation by measuring mercury concentrations in feathers of the endangered California Ridgway’s rail (formerly California...
This data set contains decomposition rates for litter of Salicornia pacifica, Distichlis spicata, and Deschampsia cespitosa buried at 7 tidal marsh sites in 2015. Sediment organic matter values were collected at a subset of sites. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
This data table contains mean decomposition rates and mean carbon:nitrogen ratios for different litter types buried in 7 marshes during 2015. Note that C:N data are repeated for low and high marsh areas at each site in the table. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
Lidar-derived digital elevation models often contain a vertical bias due to vegetation. In areas with tidal influence the amount of bias can be ecologically significant, for example, by decreasing the expected inundation frequency. We generated a corrected digital elevation mode (DEM) for Suisun marsh using a modification of the Lidar Elevation Adjustment with NDVI (LEAN) technique (Buffington et al. 2016). GPS survey data (6912 points, collected across public and private land in 2018), Normalized Difference Vegetation Index (NDVI) derived from an airborne multispectral image (June 2018), a 1 m lidar DEM from September 2018, and a 1 m canopy surface model were used to generate models of predicted bias across the...
This data table contains results for the 2014 mesocosm tests of inundation effects on decomposition. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
Fragmentation and loss of natural habitat have important consequences for wild populations and can negatively affect long-term viability and resilience to environmental change. Salt marsh obligate species, such as those that occupy the San Francisco Bay Estuary in western North America, occupy already impaired habitats as result of human development and modifications and are highly susceptible to increased habitat loss and fragmentation due to global climate change. We examined the genetic variation of the California Ridgway’s rail ( Rallus obsoletus obsoletus), a state and federally endangered species that occurs within the fragmented salt marsh of the San Francisco Bay Estuary. We genotyped 107 rails across 11...
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Clapper Rail,
Fragmentation,
Microsatellites,
Population declines,
Ridgway’s rail,
This data table contains summary data for temperature time series in near-surface sediments in high and low tidal marsh at 7 sites during 2015. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
This table contains data on dry mass remaining in a subset of Salicornia pacifica and Deschampsia cespitosa litter bags removed over a series of time points spanning 6 months. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
These datasets provide information on plant alpha, beta, and gamma diversity, and plant species abundance at several spatial scales for tidal wetlands along a salinity gradient in the San Francisco Bay-Delta and an impounded brackish wetland complex in Suisun Marsh, California. Files include diversity metrics calculated at the patch, site, and region scales, average percent cover of wetland dominant plants at the patch scale, and average percent cover of all wetland plants at the site scale. These data support the following paper: Jones, S.F., Janousek, C.N., Casazza, M.L., Takekawa, J.Y. and Thorne, K.M., 2021. Seasonal impoundment alters patterns of tidal wetland plant diversity across spatial scales. Ecosphere,...
Categories: Data;
Tags: Botany,
California,
San Francisco Bay-Delta Estuary,
USGS Science Data Catalog (SDC),
biodiversity,
This data provides county level occurrence information for all individuals used in modelling potential exposure and spread of highly pathogenic avian influenza (HPAIv) from the 2021-2022 North American outbreak. The data set contains individual identifiers and taxa information, an indicator of exposure, exposure status (Susceptible, Exposed by HPAIv detection in the county, or Exposed by secondary contact with an exposed bird), and date of first occurrence of each individual bird and that bird's exposure status within each visited county. Herein, county refers to any county, parish, borough, census area, or geographic region identified in the associated geospatial data US_CAN_AI.shp (ESRI shapefile format). Occurrence...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Canada,
Ecology,
Remote Sensing,
USGS Science Data Catalog (SDC),
United States,
This dataset contains avian survey observations across four tidal marsh areas around San Francisco Bay. Multiple surveys were conducted around both high and low tides during the winter of 2010/11. Each survey alternated between scan and focals. During scans, all observable birds were counted. During focals, the behavior of a single, randomly selected bird was observed. Water level data was collected concurrently at each site and is provided with the avian survey data. These data support the following publication: Thorne, K.M., Spragens, K.A., Buffington, K.J., Rosencranz, J.A. and Takekawa, J., 2019. Flooding regimes increase avian predation on wildlife prey in tidal marsh ecosystems. Ecology and evolution, 9(3),...
Categories: Data;
Tags: Ecology,
Emergent Tidal Marsh,
Petaluma River,
San Francisco Bay,
USGS Science Data Catalog (SDC),
This datasets summarizes small mammal trapping efforts that USGS San Francisco Bay Estuary Field Station has led, co-led, or supervised, to detect and monitor the endangered salt marsh harvest mouse (Reithrodontomys raviventris) in the northern reaches of San Francisco Bay from 1998-2014. As the salt marsh harvest mouse is listed as endangered under the Endangered Species Act, sensitive location information can be made available upon request by contacting the dataset point of contact. These data support the following publication: Marcot, B.G., Woo, I., Thorne, K.M., Freeman, C.M., and Guntenspergen, G.R., 2020. Habitat of the endangered salt marsh harvest mouse (Reithrodontomys raviventris) in San Francisco Bay....
Categories: Data;
Tags: San Francisco Bay,
San Pablo Bay,
USGS Science Data Catalog (SDC),
Wildlife Biology,
biota,
Background - Interest in developing alternative sources of renewable energy to reduce dependence on oil has increased in recent years. Some sources of renewable energy being considered will include power generation infrastructure and support activities located within continental shelf waters, and potentially within deeper waters off the U.S. Pacific coast and beyond state waters (i.e., outside three nautical miles). Currently, the Bureau of Ocean Energy Management (BOEM) is considering renewable energy proposals off the coast of Oregon, California, and Hawaii. From 1999–2002, the U.S. Geological Survey (USGS) and Humboldt State University (HSU) worked with BOEM (formely known as the Minerals Management Service,...
Decomposition of plant matter is one of the key processes affecting carbon cycling and storage in tidal wetlands. In this study, we evaluated the effects of factors related to climate change (temperature, inundation) and vegetation composition on rates of litter decay in seven tidal marsh sites along the Pacific coast. In 2014 we conducted manipulative experiments to test inundation effects on litter decay at Siletz Bay, OR and Petaluma marsh, CA. In 2015 we studied decay of litter in high and low elevation marshes at seven Pacific coast sites. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R., Thorne, K.M., Dugger, B.D. and Takekawa, J.Y., 2017. Inundation, vegetation,...
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
USGS Science Data Catalog (SDC),
Habitat biogeochemistry was assessed by measuring 31 variables in sediments, porewater, and surface waters related to mercury content, organic matter, sediment characteristics, and microbial rates of sulfate reduction, iron reduction, and methanogenesis. Fifty-six composite surface (0-2 cm) sediment cores and 32 surface water samples were collected in three wetlands in the spring and summer of 2005 and 2006.
Methylmercury (MeHg) is a globally pervasive contaminant that biomagnifies in food webs and can reach toxic concentrations in consumers at higher trophic levels, including wildlife and humans. The production of MeHg, and its subsequent entry and biomagnification in food webs, is governed by a complex suite of biogeochemical, physical, and ecological processes, resulting in spatial variation in the distribution of MeHg. To better understand the link between MeHg production in sediments and MeHg bioaccumulation in biota, we evaluated the effects of habitat biogeochemistry, food web structure, and diet composition on bioaccumulation in the wetland-obligate California black rail (Laterallus jamaicensis coturniculus)...
Diet composition can be influenced by age- and sex-related factors including an individual’s morphology, social status, and acquired skills; however, specialization may only be necessary when competition is intensified by high population densities or increased energetic demands. The western sandpiper is a small (22-35 grams) migratory shorebird that exhibits female-biased sexual size dimorphism with a 5 percent greater body size and a 15 percent longer bill in females compared to males. It is considered a generalist with a diverse diet that includes benthic invertebrates and biofilm – a thin layer of microphytobenthos, bacteria, and detritus encased in a polysaccharide-rich matrix of extracellular polymeric substances...
Categories: Data;
Tags: San Francisco Bay,
USGS Science Data Catalog (SDC),
Wildlife Biology,
ecology,
food web,
Methylmercury concentrations and stable isotope ratios were measured from back feathers of California black rails (Laterallus jamaicensis coturniculus) and six taxa of their invertebrate prey (Amphipoda, Arachnida, Coleoptera, Diptera, Gastropoda, and Hemiptera). Samples were collected from three wetlands in the spring and summer of 2005 and 2006.
This data table contains plant composition and marsh surface elevation data for 64 plots where Salicornia pacifica litter was buried at 7 sites in 2015. These data support the following publication: Janousek, C.N., Buffington, K.J., Guntenspergen, G.R. et al. Ecosystems (2017). doi:10.1007/s10021-017-0111-6. http://link.springer.com/article/10.1007/s10021-017-0111-6
Categories: Data;
Types: Citation;
Tags: Deschampsia cespitosa,
Distichlis spicata,
Pacific coast,
Salicornia pacifica,
carbon cycling,
Recent interest has increased related to developing alternative sources of renewable energy to reduce dependence on oil. Some of those sources will include power generation infrastructure and support activities located within continental shelf waters, and potentially within deeper waters off the U.S. Pacific coast and beyond state waters (i.e., outside three nautical miles). Currently, the Bureau of Ocean Energy Management (BOEM) is considering renewable energy proposals off the coast of Oregon. The 2011-2012 Pacific Continental Shelf Environmental Assessment (PaCSEA) project is intended to provide new information on species composition, distribution, abundance, seasonal variation, and habitat utilization among...
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