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Josh T Ackerman

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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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...
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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