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These data include a row for each duck nest equipped with a small video camera. We present the location of the nest, the timing of the start of hatch, the timing of the end of hatch, and the timing of the departure of the hen and ducklings from the nest. Additionally, this table includes any predators that were observed at the nest depredating eggs prior to hatch and any predators that were observed at the nest between hatch and departure from the nest. These data support the following publication: "Sitting ducklings: Timing of hatch, nest departure, and predation risk for dabbling duck broods" by Sarah H. Peterson, Joshua T. Ackerman, Mark P. Herzog, C. Alex Hartman, Rebecca Croston, Cliff L. Feldheim, and Michael...
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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...
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This dataset describes mesopredator locations (raccoons and striped skunks), dabbling duck nest locations (mallard, gadwall, and cinnamon teal), northern harrier nest locations, and random locations in relation to a set of habitat features in Suisun Marsh, California during 2016 through 2019. We designed a series of questions to link fine-scale predator movements and vulnerability of dabbling duck nests to predator encounters and egg predation. We conducted our study over a 4-year period using 41 GPS-collared raccoons and striped skunks, two of the most widespread mammalian predators of waterfowl eggs in North America, and more than 2000 monitored duck nests. Each night of movement for mesopredators contains the...
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We used free-ranging northern elephant seals as a model species to investigate maternal transfer of mercury (Hg) to pups in relation to maternal traits, including maternal blood mercury concentrations, and to quantify the links between pup lanugo mercury concentrations and maternal mesopelagic foraging behavior during gestation. We satellite tracked known-age adult females at sea during their seven-month-long foraging trip to determine maternal foraging strategies (geographic locations and diving depths) and quantified mercury concentrations in maternal blood and their pups’ blood and lanugo (which is defined as pup hair grown in utero) early in lactation when seals were hauled out. We then tested how the maternal...
This dataset contains mercury concentrations and locations of wintering red-legged kittiwakes in the western subartic Pacific Ocean. These data support the following publication: Fleishman, AB, RA Orben, N Kokubun, A Will, R Paredes, JT Ackerman, A Takahashi, AS Kitaysky, and SA Shaffer. 2019. Wintering in the Western Subarctic Pacific increases mercury contamination of red-legged kittiwakes. Environmental Science and Technology, in press.
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Western North America is a region defined by extreme gradients in geomorphology and climate, which support a diverse array of ecological communities and natural resources. The region also has extreme gradients in mercury (Hg) contamination due to a broad distribution of inorganic Hg sources. These diverse Hg sources and a varied landscape create a unique and complex mosaic of ecological risk from Hg impairment associated with differential methylmercury (MeHg) production and bioaccumulation. Understanding the landscape-scale variation in the magnitude and relative importance of processes associated with Hg transport, methylation, and MeHg bioaccumulation requires a multidisciplinary synthesis that transcends small-scale...
Categories: Publication; Types: Citation
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Identifying migration routes and fall stopover sites of cinnamon teal (Spatula cyanoptera septentrionalium) can provide a spatial guide to management and conservation efforts, and address vulnerabilities in wetland networks that support migratory waterbirds. Using high spatio-temporal resolution GSM-GPS transmitters, we tracked the fall migration of 61 cinnamon teal across western North America over three years (2017-2019). We marked cinnamon teal primarily during spring/summer in important breeding and molting regions across seven states (California, Oregon, Washington, Idaho, Utah, Colorado, and Nevada). We assessed migration routes and timing, detected 261 fall stopover sites, and identified specific ecoregions...
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This data consists of egg morphometric data from white-faced ibis. Eggs were collected in the field and then measured and dissected in the lab to obtain estimates of length, width and mass. This data supports the following publication: Herzog, M.P., Ackerman, J.T. and Hartman, C.A., 2021. Egg morphometrics and egg shape coefficients for White-faced Ibis (Plegadis chihi). The Wilson Journal of Ornithology.
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The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west limits the distribution of avian piscivore species, complicating broad comparisons across the region. Mercury risk to avian piscivores was evaluated across the western United States and Canada using a suite of avian piscivore species representing a variety of foraging strategies that together occur broadly across the region. Prey fish Hg concentrations were...
Categories: Publication; Types: Citation
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California’s Central Valley is a nexus for water resources in the state, draining the Sacramento and San Joaquin River watersheds. Urban centers, agricultural operations, and the environment all compete for limited water, and demand is expected to only increase as the population grows and agriculture intensifies. At the same time, the water supply is projected to decrease as temperatures rise, precipitation patterns change, and the frequency of extreme droughts increases. The Central Valley also provides critical wetland habitats to migratory waterbirds, and wetland managers require information on how to best use water resources to support wildlife objectives, particularly during drought. This project seeks to...
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Nest monitoring data of white-faced ibis. Data were collected at seven day intervals and provide information on success and failure of the nest during that interval. Summary vegetation and habitat data were also collected at the nest. These data support the following publication: Herzog, M.P., Ackerman, J.T., Hartman, C.A. and Browers, H., 2020. Nesting ecology of White-faced Ibis (Plegadis chihi) in Great Salt Lake, Utah. The Wilson Journal of Ornithology, 132(1), pp.134-144.
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The dataset includes three separate excel spreadsheets which provides waterbird (and predator) observations within individual survey units during the May 2019 breeding waterbird survey of south San Francisco Bay (2019WaterbirdSurveyFullData.xlsx), the total number of American avocets, black-necked stilts, and Forster's terns within each pond unit surveyed during the May 2019 survey (2019WaterbirdSurveyPondModel.xlsx), and the annual total number of nests for American avocets, black-necked stilts, and Forster's terns in south San Francisco between 2005 and 2019 (SouthBayWaterbirdNests2005-2019.xlsx). These data support the following publication: Hartman, C.A., Ackerman, J.T., Schacter, C.R., Herzog, M.P., Tarjan,...
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Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert...
Categories: Publication; Types: Citation
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These data are the raw total mercury (THg) concentrations in whole feathers, feather homogenates, and feather components (i.e., rachis, vane, calamus) that are presented in the Journal Article "Mercury concentrations vary within and among individual bird feathers: A critical evaluation and guidelines for feather use in mercury monitoring programs" in Environmental Toxicology and Chemistry by Peterson et al.
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This dataset describes responses to flushes by surveyors and predators for mallard and gadwall hens nesting on the Grizzly Island Wildlife Area, Suisun Marsh, California in 2015 through 2018. It includes the start time and duration of recesses, as well as the cause of recess initiation and responses of hens to various trapping activities at the nest site. These data support the following publication: Croston, R., Hartman, C.A., Herzog, M.P., Peterson, S.H., Kohl, J.D., Overton, C.T., Feldheim, C.L., Casazza, M.L. and Ackerman, J.T., 2021. Interrupted incubation: How dabbling ducks respond when flushed from the nest. Ecology and Evolution.
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The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3 μg/g wet weight (ww), and 10 locations an average above 1.0 μg/g ww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on...
Categories: Publication; Types: Citation
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Widespread mercury (Hg) contamination of aquatic systems in the Sierra Nevada of California, U.S., is associated with historical use to enhance gold (Au) recovery by amalgamation. In areas affected by historical Au mining operations, including the western slope of the Sierra Nevada and downstream areas in northern California, such as San Francisco Bay and the Sacramento River-San Joaquin River Delta, microbial conversion of Hg to methylmercury (MeHg) leads to bioaccumulation of MeHg in food webs, and increased risks to humans and wildlife. This study focused on developing a predictive model for THg in stream fish tissue based on geospatial data, including land use/land cover data, and the distribution of legacy...
Categories: Publication; Types: Citation
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This dataset describes nocturnal incubation recess behavior for mallard and gadwall hens nesting in Grizzly Island Wildlife Area in breeding seasons 2015-2018. It includes the frequency, start time and duration of recesses, and details a method for determining whether a recess was initiated in response to a predator at the nest using nest temperature data. These data support the following publication: Croston, R.L., Peterson, S.E., Hartman, C.A., Herzog, M.P., Feldheim, C.L., Casazza, M.L., Ackerman, J.T., 2021. Nocturnal incubation recess and flushing behavior by duck hens. Ecology and Evolution
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Eggshells of 13 waterbird species were divided in half longitudinally and the outer eggshell membrane was removed from one of the halves. Eggshell thickness was measured for both eggshell halves, both with and without the outer eggshell membrane. The eggshell membrane thickness was calculated by taking the difference between the two thickness measurements. These data support the following publication: Santolo, G.M., Peterson, S.H., Cooney, B., Hartman, C.A., Herzog, M.P. and Ackerman, J.T., 2024. Eggshell membrane thickness and its contribution to total eggshell thickness for 13 waterbird species. The Wilson Journal of Ornithology. https://doi.org/10.1676/23-00017
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This dataset includes egg total mercury concentrations, egg total mercury burden, egg length, egg width, predicted egg volume, and predicted fresh wet weight according to egg position in the laying sequence for tree swallow and house wren eggs from the Cache Creek Settling Basin and Cosumnes River Preserve, in California's Central Valley during 2018. These data support the following publication: Hartman, C.A., Ackerman, J.T., Cooney, B., and Herzog, M.P., 2024. Egg mercury concentration and egg size varies with position in the laying sequence in two songbird species. Environmental Toxicology and Chemistry.


map background search result map search result map Historical methyl mercury in San Francisco Bay The Impact of Drought on Waterbirds and Their Wetland Habitats in California’s Central Valley The timing of dabbling duckling hatch, nest departure and depredation in Suisun Marsh, California from 2015-2017 Variability of mercury concentrations among whole bird feathers, feather homogenates, and feather components quantified in California in 2017-2018 Nest Data for White-faced Ibis in Bear River Migratory Bird Refuge, Great Salt Lake, Utah in Summer 2012 Breeding Waterbird Populations in South San Francisco Bay 2005-2019 How Mallard and Gadwall Hens Nesting in Grizzly Island Wildlife Area Respond when Flushed (2015 - 2018) Nocturnal Incubation Recess and Flushing Behavior by Duck Hens Nesting in Grizzly Island Wildlife Area 2015-2018 Migration stopover ecology of cinnamon teal in western North America Egg Morphometric Data Obtained for White-faced Ibis Nesting in Bear River Migratory Bird Refuge, Great Salt Lake, Utah (2010-2012) Predator Movements and Duck Nests in Relation to Habitat Features in Suisun Marsh, CA (2016-2019) Maternal Transfer of Mercury to Northern Elephant Seal Pups Egg Membrane Thickness in 13 Waterbird Species Egg Mercury Concentration and Egg Size in Two Songbird Species Nest Data for White-faced Ibis in Bear River Migratory Bird Refuge, Great Salt Lake, Utah in Summer 2012 Egg Morphometric Data Obtained for White-faced Ibis Nesting in Bear River Migratory Bird Refuge, Great Salt Lake, Utah (2010-2012) The timing of dabbling duckling hatch, nest departure and depredation in Suisun Marsh, California from 2015-2017 Breeding Waterbird Populations in South San Francisco Bay 2005-2019 How Mallard and Gadwall Hens Nesting in Grizzly Island Wildlife Area Respond when Flushed (2015 - 2018) Nocturnal Incubation Recess and Flushing Behavior by Duck Hens Nesting in Grizzly Island Wildlife Area 2015-2018 Predator Movements and Duck Nests in Relation to Habitat Features in Suisun Marsh, CA (2016-2019) The Impact of Drought on Waterbirds and Their Wetland Habitats in California’s Central Valley Historical methyl mercury in San Francisco Bay Variability of mercury concentrations among whole bird feathers, feather homogenates, and feather components quantified in California in 2017-2018 Egg Membrane Thickness in 13 Waterbird Species Migration stopover ecology of cinnamon teal in western North America Maternal Transfer of Mercury to Northern Elephant Seal Pups