Monitoring abundance of aggregated animals (Florida manatees) using an unmanned aerial system (UAS)
Holly H Edwards, Jeffrey A. Hostetler, Bradley M Stith, Julien Martin
2021, Scientific Reports (11)
Imperfect detection is an important problem when counting wildlife, but new technologies such as unmanned aerial systems (UAS) can help overcome this obstacle. We used data collected by a UAS and a Bayesian closed capture-mark-recapture model to estimate abundance and distribution while accounting for imperfect detection...
Estimating abundance and simulating fertility control in feral burros
Jay V. Gedir, James W. Cain III, Bruce C. Lubow, Talesha Karish, David K. Delaney, Gary W. Roemer
2021, Journal of Wildlife Management (85) 1187-1199
Overabundant populations of feral equids are negatively impacting rangelands in the western United States. To effectively manage these populations, robust estimates of abundance and demography are necessary, as well as cost-effective methods of reducing abundance. We used a double-observer-sightability aerial survey method to estimate the number of feral burros (Equus...
Permafrost thaw in northern peatlands: Rapid changes in ecosystem and landscape functions
David Olefeldt, Liam Hefferman, Miriam C. Jones, A. Britta Sannel, Claire C. Treat, Merritt R. Turetsky
2021, Book chapter, Ecosystem collapse and climate change
Peatlands within the northern permafrost region cover approximately 2 million km2 and are characterized by organic soils that can be several meters thick, and a fine-scale mosaic of permafrost and non-permafrost landforms interspersed by shallow ponds and lakes. Ongoing permafrost thaw is transforming these peatlands, causing abrupt changes to their morphology,...
Magnetic surveys with unmanned aerial systems: Software for assessing and comparing the accuracy of different sensor systems, suspension designs and compensation methods
Leon Kaub, Gordon Keller, Claire Bouligand, Jonathan M.G. Glen
2021, Geochemistry, Geophysics, Geosystems (G-Cubed) (22)
A typical problem for magnetic surveys with small Unmanned Aerial Systems (sUAS) is the heading error caused by undesired magnetic signals that originate from the aircraft. This can be addressed by suspending the magnetometers on sufficiently long tethers. However, tethered payloads require skilled pilots and are difficult...
Extreme events trigger terrestrial and marine ecosystem collapses: A tale of two regions
Katinka X. Ruthrof, Joseph B. Fontaine, David D. Breshears, Jason P. Field, Craig D. Allen
2021, Book chapter, Ecosystem collapse and climate change
We outline the multiple, cross-scale, and complex consequences of terrestrial and marine ecosystem heatwaves in two regions on opposite sides of the planet: the southwestern USA and southwestern Australia, both encompassing Global Biodiversity Hotspots, and where ecosystem collapses or features of it have occurred in the past two decades. We...
Interacting effects of density-dependent and density-independent factors on growth rates in southwestern Cutthroat Trout populations
Brock M. Huntsman, Abigail Lynch, Colleen A. Caldwell
2021, Transactions of the American Fisheries Society (150) 651-664
Density-dependent (DD) and density-independent (DI) effects play an important role in shaping fish growth rates, an attribute that correlates with many life history traits in fishes. Consequently, understanding the extent to which DD and DI effects influence growth rates is valuable for fisheries assessments because it can inform managers about...
Comparison of historical water temperature measurements with landsat analysis ready data provisional surface temperature estimates for the Yukon River in Alaska
Carson Baughman, Jeff Conaway
2021, Remote Sensing (13)
Water temperature is a key element of freshwater ecological systems and a critical element within natural resource monitoring programs. In the absence of in situ measurements, remote sensing platforms can indirectly measure water temperature over time and space. The Earth Resources Observation and Science (EROS) Center has processed archived Landsat...
Sediment transport, turbidity, and dissolved oxygen responses to annual streambed drawdowns for downstream fish passage in a flood control reservoir
Liam N. Schenk, Heather M. Bragg
2021, Journal of Environmental Management (295)
Sediment transport, turbidity, and dissolved oxygen were evaluated during six consecutive water years (2013–2018) of drawdowns of a flood control reservoir in the upper Willamette Valley, Oregon, USA. The drawdowns were conducted to allow volitional passage of endangered juvenile chinook salmon through the dam's regulating outlets by lowering the reservoir elevation...
Egg retention of high-latitude sockeye salmon (Oncorhynchus nerka) in the Pilgrim River, Alaska, during the Pacific marine heatwave of 2014–2016
Michael P. Carey, Vanessa R. von Biela, Ashley Dunker, Kevin D. Keith, Merlyn Schelske, Charlie Lean, Christian E. Zimmerman
2021, Polar Biology (44) 1643-1654
Ocean and freshwater conditions can influence spawning success of Pacific salmon (Oncorhynchus spp.) by governing the energy content of fish at the start of and during the spawning migration. Ocean conditions determine the energy stores of fish at the freshwater entry, while freshwater conditions determine how quickly stored energy is depleted...
New geochemical tools for investigating resource and energy functions at deep-sea cold seeps using amino-acid δ15N in chemosymbiotic mussels (Bathymodiolus childressi)
Natasha Vokhshoori, Matt McCarthy, Hilary Close, Amanda Demopoulos, Nancy G. Prouty
2021, Geobiology (19) 601-617
In order to reconstruct the ecosystem structure of chemosynthetic environments in the fossil record, geochemical proxies must be developed. Here, we present a suite of novel compound-specific isotope parameters for tracing chemosynthetic production with a focus on understanding nitrogen dynamics in deep-sea cold seep environments. We examined the chemosymbiotic bivalve Bathymodiolus...
Nutrient limitation of algae and macrophytes in streams: Integrating laboratory bioassays, field experiments, and field data
Christopher A. Mebane, Andrew M. Ray, Amy M Marcarelli
2021, PLoS ONE (16)
Successful eutrophication control strategies need to address the limiting nutrient. We conducted a battery of laboratory and in situ nutrient-limitation tests with waters collected from 9 streams in an agricultural region of the upper Snake River basin, Idaho, USA. Laboratory tests used the green alga Raphidocelis subcapitata, the macrophyte Lemna minor (duckweed) with...
Land-based sediment sources and transport to southwest Puerto Rico coral reefs after Hurricane Maria, May 2017 to June 2018
Renee K. Takesue, Clark E. Sherman, Aaron O. Reyes, Olivia M. Cheriton, Natalia I. Ramirez, Roberto Viqueira Rios, Curt D. Storlazzi
2021, Estuarine, Coastal and Shelf Science (259)
The effects of runoff from land on nearshore ecosystems, including coral reef communities, are influenced by both sediment supply and removal by coastal processes. Integrated studies across the land-sea interface describing sources and transport of terrestrial sediment and its nearshore fate allow reef protection initiatives to target key onshore and offshore areas....
When hazard avoidance is not an option: Lessons learned from monitoring the postdisaster Oso landslide, USA
Mark E. Reid, Jonathan W. Godt, Richard G LaHusen, Stephen L Slaughter, Thomas C. Badger, Brian D. Collins, William H. Schulz, Rex L. Baum, Jeffrey A. Coe, Edwin L Harp, Kevin M. Schmidt, Richard M. Iverson, Joel B. Smith, Ralph A. Haugerud, David L. George
2021, Landslides (18) 2993-3009
On 22 March 2014, a massive, catastrophic landslide occurred near Oso, Washington, USA, sweeping more than 1 km across the adjacent valley flats and killing 43 people. For the following 5 weeks, hundreds of workers engaged in an exhaustive search, rescue, and recovery effort directly in...
Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert
Molly J Bechtel, K. Kristina Drake, Todd Esque, Nathan C Nieto, Jeffrey T. Foster, Mike B Teglas
2021, Vector-Borne and Zoonotic Diseases (21) 635-637
Ticks transmit pathogens and parasitize wildlife in turn causing zoonotic diseases in many ecosystems. Argasid ticks, such as Ornithodoros spp., harbor and transmit Borrelia spp., resulting in tick-borne relapsing fever (TBRF) in people. In the western United States, TBRF is typically associated with the bite of...
Regional occurrence of aqueous tungsten and relations with antimony, arsenic and molybdenum concentrations (Sardinia, Italy)
Rosa Cidu, Riccardo Biddau, Franco Frau, Richard Wanty, Stefano Naitza
2021, Journal of Geochemical Exploration (229)
Tungsten (W) is rarely found in natural waters, yet it can be introduced into the food chain and cause potentially toxic effects. Uptake of W by plants and vegetables, or trace presence of W in drinking water are...
The marine terraces of Santa Cruz Island, California: Implications for glacial isostatic adjustment models of last-interglacial sea-level history
Daniel R. Muhs, R. Randall Schumann, Lindsey T. Groves, Kathleen R. Simmons, Christopher R. Florian
2021, Geomorphology (389)
Glacial isostatic adjustment (GIA) models hypothesize that along coastal California, last interglacial (LIG, broadly from ~130 to ~115 ka) sea level could have been as high as +11 m to +13 m, relative to present, substantially higher than the commonly estimated elevation of +6 m....
Physiomorphic transformation in extreme endurance migrants: Revisiting the case of bar-tailed godwits preparing for trans-pacific flights
Theunis Piersma, Robert E. Gill Jr., Daniel R. Ruthrauff
2021, Frontiers in Ecology and Evolution (9)
In a 1998 paper entitled “Guts don’t fly: small digestive organs in obese bar-tailed godwits,” Piersma and Gill (1998) showed that the digestive organs were tiny and the fat loads huge in individuals suspected of embarking on a non-stop flight from Alaska to New Zealand. It was suggested that prior...
Assessment of a conservative mixing model for the evaluation of constituent behavior below river confluences, Elqui River Basin, Chile
Catalina Rossi, Jorge Oyarzun, Pablo Pasten, Robert L. Runkel, Jorge Núñez, Denisse Duhalde, Hugo Maturana, Eduardo Rojas, José L. Arumí, Daniela Castillo, Ricardo Oyarzun
2021, River Research and Applications (37) 967-978
Fate and transport modeling of water-borne contaminants is a data demanding and costly endeavor, requiring considerable expes such, it becomes important to know when a complex modeling approach is required, and when a simpler approach is adequate. This is the main objective herein, where a conservative mixing model is used...
Prioritizing restoration areas to conserve multiple sagebrush-associated wildlife species
Courtney Jean Duchardt, Adrian P. Monroe, Julie A. Heinrichs, Michael S. O’Donnell, David R. Edmunds, Cameron L. Aldridge
2021, Biological Conservation (260)
Strategic restoration of altered habitat is one method for addressing worldwide biodiversity declines. Within the sagebrush steppe of western North America, habitat degradation has been linked to declines in many species, making restoration a priority for managers; however, limited funding, spatiotemporal variation in restoration success, and the need to manage for diverse...
Enhanced terrestrial runoff during Oceanic Anoxic Event 2 on the North Carolina Coastal Plain, USA
Christopher M Lowery, Jean Self-Trail, Craig Barrie
2021, Climate of the Past (17) 1227-1242
A global increase in the strength of the hydrologic cycle drove an increase in the flux of terrigenous sediments into the ocean during the Cenomanian–Turonian Oceanic Anoxic Event 2 (OAE2) and was an important mechanism driving nutrient enrichment and thus organic carbon burial. This global change is primarily known from isotopic...
Extensibility of U-net neural network model for hydrographic feature extraction and implications for hydrologic modeling
Larry V. Stanislawski, Ethan J. Shavers, Shaowen Wang, Zhe Jiang, E. Lynn Usery, Evan Moak, Alexander Duffy, Joel Schott
2021, Remote Sensing (13)
Accurate maps of regional surface water features are integral for advancing ecologic, atmospheric and land development studies. The only comprehensive surface water feature map of Alaska is the National Hydrography Dataset (NHD). NHD features are often digitized representations of historic topographic map blue lines and may be outdated. Here we...
Assessing habitat change and migration of barrier islands
Nicholas Enwright, Lei Wang, P. Soupy Dalyander, Hongqing Wang, Michael Osland, Rangley C. Mickey, Robert L. Jenkins III, Elizabeth Godsey
2021, Estuaries and Coasts (44) 2073-2086
Barrier islands are dynamic environments that experience gradual change from waves, tides, and currents, and rapid change from extreme storms. These islands are expected to change drastically over the coming century due to accelerated sea-level rise and changes in frequency and intensity of storm events. The dynamic nature of barrier...
Ecogeographic variation and taxonomic boundaries in Large Treeshrews (Scandentia, Tupaiidae: Tupaia tana Raffles, 1821) from Southeast Asia
Maya M. Juman, Neal Woodman, Link E. Olson, Eric J. Sargis
2021, Journal of Mammalogy (102) 1054-1066
The Large Treeshrew, Tupaia tana Raffles, 1821, is a small mammal (~205 g) from Southeast Asia with a complicated taxonomic history. Currently, 15 subspecies are recognized from Borneo, Sumatra, and smaller islands, and many were originally differentiated based on minor pelage differences and small sample sizes. We explored intraspecific variation in T. tana using...
Strategic testing approaches for targeted disease monitoring can be used to inform pandemic decision-making
James D. Nichols, Tiffany L. Bogich, Emily Howerton, Ottar N. Bjornstad, Rebecca K. Borchering, Matthew J. Ferrari, Murali Haran, Christopher P. Jewell, Kim M. Pepin, William J. M. Probert, Juliet R. C. Pulliam, Michael C. Runge, Michael J. Tildesley, Cecile Viboud, Katriona Shea
2021, PLoS Biology (19)
More than 1.6 million Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) tests were administered daily in the United States at the peak of the epidemic, with a significant focus on individual treatment. Here, we show that objective-driven, strategic sampling designs and analyses can maximize information gain at the population level,...
Detecting subtle change from dense landsat time series: Case studies of mountain pine beetle and spruce beetle disturbance
Su Ye, John Rogan, Zhe Zhu, Todd Hawbaker, Sarah J. Hart, Robert A. Andrus, Arjan J.H. Meddens, Jeffery A. Hicke, J. Ronald Eastman, Dominik Kulakowski
2021, Remote Sensing of Environment (263)
In contrast to abrupt changes caused by land cover conversion, subtle changes driven by a shift in the condition, structure, or other biological attributes of land often lead to minimal and slower alterations of the terrestrial surface. Accurate mapping and monitoring of subtle change are crucial for an early warning...
