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Scale growth rates and scale circulus deposition rates of marine-stage Atlantic salmon Salmo salar raised under semi-natural conditions Scale growth rates and scale circulus deposition rates of marine-stage Atlantic salmon Salmo salar raised under semi-natural conditions
Scale circuli yield valuable information about the life history, age, and growth of a fish. However, because circuli formation is influenced by somatic growth, the rate at which circuli are formed and the factors influencing these rates must be taken into account for the given life stage of the study species. Scales were collected from Atlantic salmon raised in marine net pens off of the...
Authors
Erin Peterson, Timothy F. Sheehan, Joseph D. Zydlewski
Imaging the next Cascadia earthquake: Optimal design for a seafloor GNSS- A network Imaging the next Cascadia earthquake: Optimal design for a seafloor GNSS- A network
The Cascadia subduction zone in the Pacific Northwest of the United States of America capable of producing magnitude ∼9 earthquakes, likely often accompanied by tsunamis. An outstanding question in this region is the degree and spatial extent of interseismic strain accumulation on the subduction megathrust. Seafloor geodetic methods combining GNSS and underwater acoustic ranging (GNSS-A)...
Authors
Eileen L. Evans, Sarah E. Minson, David Chadwell
White-nose Syndrome and environmental correlates to landscape-scale bat presence White-nose Syndrome and environmental correlates to landscape-scale bat presence
Over the past 13 years, White-nose Syndrome (WNS) has caused North American bat population declines and shifted community structure towards species less or unaffected by the disease. Mist-netting, acoustic surveys, and cave count data have been used to document changes in bat presence and activity through site-specific, pre- and post-WNS studies. Management and survey guidance often must...
Authors
Elaine L. Barr, Alexander Silvis, Mike P. Armstrong, W. Mark Ford
Migration stopover ecology of Cinnamon Teal in western North America Migration stopover ecology of Cinnamon Teal in western North America
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 spatiotemporal resolution GPS-GSM transmitters, we analyzed 61 fall migration tracks across western North America during...
Authors
Desmond Alexander Mackell, Michael L. Casazza, Cory T. Overton, J. Patrick Donnelly, David Olson, Fiona McDuie, Joshua T. Ackerman, John M. Eadie
A stable isotope record of late Quaternary hydrologic change in the northwestern Brooks Range, Alaska (eastern Beringia) A stable isotope record of late Quaternary hydrologic change in the northwestern Brooks Range, Alaska (eastern Beringia)
A submillennial-resolution record of lake water oxygen isotope composition (δ18O) from chironomid head capsules is presented from Burial Lake, northwest Alaska. The record spans the Last Glacial Maximum (LGM; ~20–16k cal a bp) to the present and shows a series of large lake δ18O shifts (~5‰). Relatively low δ18O values occurred during a period covering the LGM, when the lake was a...
Authors
Amanda L. King, Lesleigh Anderson, Mark B. Abbott, Mary Edwards, Matthew S. Finkenbinder, Bruce P. Finney, Matthew J. Wooller
Elevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels Elevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels
Measurements of the natural radiocarbon content of methane (14C-CH4) dissolved in seawater and freshwater have been used to investigate sources and dynamics of methane. However, during investigations along the Atlantic, Pacific, and Arctic Ocean Margins of the United States, as well as in the North American Great Lakes, some samples revealed highly elevated 14C-CH4 values, as much as 4–5...
Authors
D.J. Joung, Carolyn D. Ruppel, J. Southon, John D. Kessler
Shallow marine ecosystem collapse and recovery during the Paleocene-Eocene Thermal Maximum Shallow marine ecosystem collapse and recovery during the Paleocene-Eocene Thermal Maximum
The Paleocene-Eocene Thermal Maximum (PETM), the most well-studied transient hyperthermal event in Earth history, is characterized by prominent and dynamic changes in global marine ecosystems. Understanding such biotic responses provides valuable insights into future scenarios in the face of anthropogenic warming. However, evidence of the PETM biotic responses is largely biased towards...
Authors
Skye Y Tian, Moriaki Yasuhara, Huai-Hsuan M Huang, Fabien L. Condamine, Marci M. Robinson
Saltwater intrusion intensifies coastal permafrost thaw Saltwater intrusion intensifies coastal permafrost thaw
Surface effects of sea-level rise (SLR) in permafrost regions are obvious where increasingly iceless seas erode and inundate coastlines. SLR also drives saltwater intrusion, but subsurface impacts on permafrost-bound coastlines are unseen and unclear due to limited field data and the absence of models that include salinity-dependent groundwater flow with solute exclusion and freeze-thaw...
Authors
Julia Guimond, Aaron Mohammad, Michelle A. Walvoord, Victor F. Bense, Barret L. Kurylyk
Episodic nutrient addition affects water column nutrient processing rates in river-to-lake transitional zones Episodic nutrient addition affects water column nutrient processing rates in river-to-lake transitional zones
Storm-driven nutrient loading from tributaries can fuel eutrophication in nearshore and open water areas of lentic ecosystems. However, nutrient processing in river-to-lake transitional zones can substantially alter the amount and composition of nutrients transported to lakes from upstream surface waters. We measured the removal of nutrients and dissolved organic carbon (DOC) from the...
Authors
Nolan J.T. Pearce, James H. Larson, Mary Anne Evans, Paul C. Frost, Marguerite A. Xenopoulos
Establishment of baseline cytology metrics in nestling American kestrels (Falco sparverius): Immunomodulatory effects of the flame retardant isopropylated triarylphosphate isomers Establishment of baseline cytology metrics in nestling American kestrels (Falco sparverius): Immunomodulatory effects of the flame retardant isopropylated triarylphosphate isomers
Avian populations must mount effective immune responses upon exposure to environmental stressors such as avian influenza and xenobiotics. Although multiple immune assays have been tested and applied to various avian species, antibody-mediated immune responses in non-model avian species are not commonly reported due to the lack of commercially available species-specific antibodies. The...
Authors
Jill Jenkins, Brooke A Baudoin, Darren Johnson, Kim J. Fernie, Heather M. Stapelton, Natalie Karouna-Renier
Integrating regional and local monitoring data and assessment tools to evaluate habitat conditions and inform river restoration Integrating regional and local monitoring data and assessment tools to evaluate habitat conditions and inform river restoration
RRestoring degraded rivers requires initial assessment of the fluvial landscape to identify stressors and riverine features that can be enhanced. We associated local-scale river habitat data collected using standardized national monitoring tools with modeled regional water temperature and flow data on mid-sized northwest U.S. rivers (30–60 m wide). We grouped these rivers according to...
Authors
Francine H. Mejia, Jason M Connor, Phil R Kaufmann, Christian E. Torgersen, Eric K Berntsen, Todd Andersen
Honey bee (Apis mellifera) colonies benefit from grassland/ pasture while bumble bee (Bombus impatiens) colonies in the same landscapes benefit from non-corn/soybean cropland Honey bee (Apis mellifera) colonies benefit from grassland/ pasture while bumble bee (Bombus impatiens) colonies in the same landscapes benefit from non-corn/soybean cropland
Agriculturally important commercially managed pollinators including honey bees (Apis mellifera L., 1758) and bumble bees (Bombus impatiens Cresson, 1863) rely on the surrounding landscape to fulfill their dietary needs. A previous study in Europe demonstrated that managed honey bee foragers and unmanaged native bumble bee foragers are associated with different land uses. However, it is...
Authors
Gabriela Quinlan, Megan Milbrath, Clint R.V. Otto, Rufus Isaacs