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10Be/9Be and 26Al/10Be support a late Miocene burial age for basal Gray Fossil Site sediments 10Be/9Be and 26Al/10Be support a late Miocene burial age for basal Gray Fossil Site sediments
We provide 2 independent radioisotopic age estimates for cored basal sediments of the Gray Fossil Site using cosmogenic nuclides. The first estimate uses meteoric 10Be/9Be from the bottom of the GFS-1 core, as well as from modern local grasses, to constrain the deposition of basal GFS sinkhole complex sediments to 6.60 ± 0.85 Ma. We corroborated this age estimate using in-situ 10Be and...
Authors
William Elijah Odom, Darryl E. Granger, Steven C. Wallace
Diverging fish biodiversity trends in cold and warm rivers and streams Diverging fish biodiversity trends in cold and warm rivers and streams
Worldwide, freshwater systems contain more than 18,000 fish species1,2,3, which are critical to the functioning of these ecosystems4 and are vital cultural and economic resources to humans5,6,7; despite this value, fish biodiversity is at risk globally8,9. In the USA, leading threats to fish communities in rivers and streams include climate change and invasive fish introductions and game...
Authors
Samantha L. Rumschlag, Brian Gallagher, Ryan Hill, Ralf B. Schafer, Travis S. Schmidt, Taylor Woods, Darin A. Kopp, Michael Dumelle, Jason Rohr, Frederik De Laender, Joel Hoffman, Jonathan Behrens, Ryan Lepak, Devin Jones, Michael Mahon
Linking stream-reach nitrogen loads and groundwater “reachsheds” to inform wastewater-nitrogen management actions, Cape Cod, Massachusetts Linking stream-reach nitrogen loads and groundwater “reachsheds” to inform wastewater-nitrogen management actions, Cape Cod, Massachusetts
Study RegionCape Cod, Massachusetts, U.S.A.Study FocusAnthropogenic nitrogen (N) is a key factor in degrading groundwater and surface-water quality, particularly in coastal New England where onsite wastewater systems are prevalent. This study evaluated whether direct N-load measurements in streams on Cape Cod, Massachusetts, coupled with flow-path information from groundwater-flow models...
Authors
Timothy D. McCobb, Denis R. LeBlanc, Jeffrey R. Barbaro, Marcel Belaval
Evaluation of juvenile salmon behavior to inform downstream fish passage development at a high head dam Evaluation of juvenile salmon behavior to inform downstream fish passage development at a high head dam
Fish passage development is a priority at Tieton Dam, on the Tieton River in Washington state, because passage options were not included when the dam was constructed nearly 100 years ago. To inform downstream passage design, we conducted a study to evaluate migration and near-dam behavior of juvenile salmon. The primary goal of the study was to determine how fish approached the dam and...
Authors
Tobias J. Kock, Joseph Mitchell Morse, Caitlin Louise Stockwell, Amy C. Hansen
Seaward movements and mortality of Atlantic salmon Salmo salar L. kelts in the Penobscot River, Maine Seaward movements and mortality of Atlantic salmon Salmo salar L. kelts in the Penobscot River, Maine
The Atlantic salmon Salmo salar L. is an endangered species in the United States, but post-spawn downstream movements remain poorly understood. We conducted a 2-year acoustic telemetry study to characterize downstream movements and to quantify apparent mortality and downstream passage of post-spawn adults (kelts) in the Penobscot River, Maine, USA (N = 112). The majority of tagged S...
Authors
Carolyn A. Merriam, Danielle M. Frechette, Joseph D. Zydlewski
Sequoia and Sequoiadendron: Two paleoendemic megatrees with markedly different adaptive responses to recent high-severity fires Sequoia and Sequoiadendron: Two paleoendemic megatrees with markedly different adaptive responses to recent high-severity fires
Premise Coast redwood (Sequoia sempervirens) and giant sequoia (Sequoiadendron giganteum) are two iconic paleoendemic species with limited distributions, well known for their spectacular size. Recently, they have been exposed to high-severity crown fires, with starkly contrasting responses.Methods We used all available published literature and field observations to understand the...
Authors
Jon Keeley, Juli G. Pausas
Longer rorqual whale mothers produce more female offspring Longer rorqual whale mothers produce more female offspring
Multiple hypotheses have arisen that predict how mammals with the ability to adapt fetal sex ratios should invest in male versus female offspring to maximize inclusive fitness, but large wild-population datasets necessary for testing these hypotheses are challenging to collect. We used whaling data (n = 209 254 sexed fetuses from seven rorqual whale species) to test whether mothers with...
Authors
Zoe R. Rand, Trevor A. Branch, Sarah J. Converse
Long-term monitoring of island night lizards on San Nicolas Island Long-term monitoring of island night lizards on San Nicolas Island
We describe the results of long-term population monitoring of the island night lizard Xantusia riversiana on San Nicolas Island, California, following the species' removal from the U.S. Endangered Species list in 2014. Monitoring activities were carried out from October 2014 through November 2023, but we also incorporate data from earlier work dating back to 1993. Because of habitat loss...
Authors
Charles A. Drost, Patrick M. Kleeman, Charles B. Yackulic, Brian J. Halstead, Gary M. Fellers
CaDAVEr: A metagenome-assembled genome catalog of microbial decomposers across vertebrate environments CaDAVEr: A metagenome-assembled genome catalog of microbial decomposers across vertebrate environments
Microbial degradation of organic matter is a fundamental Earth process, yet a mechanistic understanding of microbial metabolisms and successional ecology involved in decomposition remains poorly understood. Here, we announce the recovery of 277 cadaver-associated soil metagenome-assembled genomes to enhance our understanding of vertebrate decomposition microbial processes.
Authors
Valerie A. Seitz, Bridget B. McGivern, Michael Shaffer, Mikayla A. Borton, Aeriel D. Belk, Parsa Ghadermazi, Cameron Martino, Liat Shenhav, Anru R. Zhang, Pixu Shi, Alexandra Emmons, Heather Deel, Zhenjiang Zech Xu, Victoria Nieciecki, Qiyun Zhu, Kalen Cantrell, Asa Ben-Hur, Sasha C. Reed, Greg C. Humphry, Gail Ackermann, Daniel McDonald, Siu Hung Chan, Melissa Connor, Derek A. Boyd, Jake Smith, Jenna M.S. Watson, Giovanna Vidoli, Dawnie Steadman, Aaron M. Lynne, Sibyl Bucheli, David O. Carter, Zachary M. Burcham, Rob Knight, Kelly C. Wrighton, Jessica L. Metcalf
Pit tag application in native freshwater mussels: Case studies across small, medium, and large rivers Pit tag application in native freshwater mussels: Case studies across small, medium, and large rivers
Since their first use in the mid-1980s, external passive integrated transponder (PIT) tags have facilitated innovative investigations into multiple biological traits of animals. For native freshwater mussels, PIT tags are frequently used in capture-mark-recapture applications because they allow repeated, noninvasive sampling, are easy to apply, have high retention rates, and have...
Authors
Jeremy S. Tiemann, Matthew J. Ashton, Sarah A. Douglass, Alison P. Stodola, Rachel M. Vinsel, Teresa J. Newton
Breeder turnover creates allelic variation in groups of gray wolves Breeder turnover creates allelic variation in groups of gray wolves
Genetic diversity is an important driver affecting the health of wildlife populations. In cooperatively breeding species, human impacts and breeder turnover can affect genetic diversity in groups. We generally do not have strong inferences about how the genetic composition of a group changes through time as individuals are lost (e.g., die, emigrate) or adopted (e.g., immigrate). I wanted...
Authors
David Edward Ausband
Fluid inclusion constraints on the geometry of the magmatic plumbing system beneath Mauna Loa – Part 2: Xenoliths Fluid inclusion constraints on the geometry of the magmatic plumbing system beneath Mauna Loa – Part 2: Xenoliths
Mauna Loa volcano erupts crystal-poor material at its summit and more crystal-rich material on its rift zones. Some of the more olivine-rich lava flows contain xenoliths with diverse mineralogy, including cumulate harzburgites with high-Mg# orthopyroxenes and high-Fo olivines (both > 84). Previous experimental work and thermodynamic modelling has proposed that high-Mg# orthopyroxenes...
Authors
Penny E. Wieser, Matthew Gleeson, Berenise Rangel, Charlotte DeVitre, Alexander T. Bearden, Kendra J. Lynn, Paula Antoshechkina, Amy Gaffney, Brian Monteleone