Wintering in the western subarctic pacific increases mercury contamination of Red-legged Kittiwakes
Abram S Fleishman, Rachael Orben, Nobuo Kokubun, Alexis Will, Rosana Paredes, Joshua T. Ackerman, Akinori Takahashi, Alexander Kitaysky, Scott A. Shaffer
2020, Environmental Science & Technology (53) 13398-13407
Marine methylmercury concentrations vary geographically and with depth, exposing organisms to different mercury levels in unique habitats. Red-legged kittiwakes (Rissa brevirostris), a specialist predator, forage on fish and invertebrates from the mesopelagic zone, a part of the ocean with elevated methylmercury concentrations. We used kittiwakes as bioindicators of...
Petroleum hydrocarbons in semipermeable membrane devices deployed in the Northern Gulf of Mexico and Florida keys following the Deepwater Horizon incident
Timothy Bargar, David A. Alvarez, Scott A. Stout
2020, Marine Pollution Bulletin (150)
The Deepwater Horizon (DWH) oil spill from April to July of 2010 contaminated Gulf of Mexico waters through release of an estimated 4.1 × 106 barrels of oil. Beginning in June of 2010, semipermeable membrane devices (SPMDs) were deployed near areas with sensitive marine habitats (Alabama Alps and Western Shelf) potentially exposed to that oil....
Calibration analysis and noise estimates of WWSSN Station ALQ (Albuquerque, New Mexico)
Adam T. Ringler, David C. Wilson, Emily Wolin, Tyler Storm, L. D. Sandoval
2020, Seismological Research Letters (91) 1359-1366
World‐Wide Standardized Seismograph Network (WWSSN) records contain daily calibration pulses that can be used to retrieve the magnification as well as the response of the instrument for a given day record. We analyze a select number of long‐period vertical (LPZ) records from WWSSN station ALQ (Albuquerque, New Mexico). Although we...
Survival and conflict behavior of American black bears after rehabilitation
Coy D Blair, Lisa I Muller, Joseph D. Clark, William H Stiver
2020, Journal of Wildlife Management (84) 75-84
Wildlife agencies face difficult situations when orphaned or injured American black bear (Ursus americanus ) cubs (<12 months old) or yearlings (≥12 and <24 months old) are captured. One option is bear rehabilitation, the care and feeding of cubs or yearlings in a semi‐natural environment, followed by release. Unfortunately, the survival...
#EarthquakeAdvisory: Exploring discourse between government officials, news media and social media during the Bombay Beach 2016 Swarm
Sara K. McBride, Andrea L. Llenos, Morgan T. Page, Nicholas van der Elst
2020, Seismological Research Letters (91) 438-451
Communicating probabilities of natural hazards to varied audiences is a notoriously difficult task. Many of these challenges were encountered during the 2016 Bombay Beach, California, swarm of ~100 2≤M≤4.3 earthquakes, which began on 26 September 2016 and lasted for several days. The swarm’s proximity to the...
Grazing-induced changes to biological soil crust cover mediate hillslope erosion in a long-term exclosure experiment
Stephen E. Fick, Jayne Belnap, Michael C. Duniway
2020, Rangeland Ecology & Management (73) 61-72
Dryland ecosystems are particularly vulnerable to erosion generated by livestock grazing. Quantifying this risk across a variety of landscape settings is essential for successful adaptive management, particularly in light of a changing climate. In the Upper Colorado River Basin, there are...
Vulnerability of resource-users in Louisiana’s oyster fishery to environmental hazards
A. T. Humphries, L. Josephs, Megan K. LaPeyre, S. A. Hall, R.D. Beech
2020, Ecology and Society (24)
Knowledge of vulnerability provides the foundation for developing actions that minimize impacts on people while maximizing the sustainability of ecosystem goods and services. As a result, it is becoming increasingly important to determine how resource-dependent people are vulnerable to environmental hazards. This is particularly true in coastal Louisiana where the...
Isotopic and geochemical assessment of the sensitivity of groundwater resources of Guam, Mariana Islands, to intra- and inter-annual variations in hydroclimate
Lakin Beal, Corinne I. Wong, Kaylyn K Bautista, John W. Jenson, Jay L. Banner, Mark A Lander, Stephen B. Gingerich, Judson W. Partin, Ben Hardt, N.H. van Oort
2020, Journal of Hydrology (568) 174-183
Assessing the sensitivity of groundwater systems to hydroclimate variability is critical to sustainable management of the water resources of Guam, US territory. We assess spatial and temporal variability of isotopic and geochemical compositions of vadose and phreatic groundwater sampled from cave drip sites and production wells, respectively, to better understand the vulnerability of the...
Does vegetation change over 28 years affect habitat use and reproductive success?
Karolina Fierro-Calderón, Thomas E. Martin
2020, The Auk (137) 1-9
Individuals should prefer and use habitats that confer high fitness, but habitat use is not always adaptive. Vegetation in natural landscapes changes gradually and the ability of species to adaptively adjust their habitat use to long-term changes is largely unstudied. We studied nest patch and territory use over 28 yr...
Nonlinear reaction–diffusion process models improve inference for population dynamics
Xinyi Lu, Perry J. Williams, Mevin Hooten, James A. Powell, Jamie N. Womble, Michael R. Bower
2020, Environmetrics (31)
Partial differential equations (PDEs) are a useful tool for modeling spatiotemporal dynamics of ecological processes. However, as an ecological process evolves, we need statistical models that can adapt to changing dynamics as new data are collected. We developed a model that combines an ecological diffusion equation and logistic growth to...
Change points in annual peak streamflows: Method comparisons and historical change points in the United States
Karen R. Ryberg, Glenn A. Hodgkins, Robert W. Dudley
2020, Journal of Hydrology (583)
Change-point, or step-trend, detection is an active area of research in statistics and an area of great interest in hydrology because change points may be evidence of natural or anthropogenic changes in climatic, hydrologic, or landscape processes. A common change-point technique is the Pettitt test; however, many change-point methods are...
Hydrologic modeling for flow-ecology science in the Southeastern United States and Puerto Rico
Peter V. Caldwell, Jonathan G. Kennen, Ernie F. Hain, Stacy A.C. Nelson, Ge Sun, Steven G. McNulty
2020, General Technical Report SRS-246
An understanding of the applicability and utility of hydrologic models is critical to support the effective management of water resources throughout the Southeastern United States (SEUS) and Puerto Rico (PR). Hydrologic models have the capacity to provide an estimate of the quantity of available water at ungauged locations (i.e., areas...
Pulse sediment event does not impact the metabolism of a mixed coral reef community
Keisha Bahr, Ku’ulei Rodgers, Paul Jokiel, Nancy G. Prouty, Curt D. Storlazzi
2020, Ocean and Coastal Management (184)
Sedimentation can bury corals, cause physical abrasion, and alter both spectral intensity and quality; however, few studies have quantified the effects of sedimentation on coral reef metabolism in the context of episodic sedimentation events. Here, we present the first study to measure coral community metabolism - calcification and photosynthesis -...
Variation in selective regimes drives intraspecific variation in life-history traits and migratory behaviour along an elevational gradient
Carl G. Lundblad, Courtney J. Conway
2020, Journal of Animal Ecology (89) 397-411
Comparative studies, across and within taxa, have made important contributions to our understanding of the evolutionary processes that promote phenotypic diversity. Trait variation along geographic gradients provides a convenient heuristic for understanding what drives and maintains diversity. Intraspecific trait variation along latitudinal gradients is well-known, but elevational variation in...
Semi-automated bathymetric spectral decomposition delineates the impact of mass wasting on the morphological evolution of the continental slope, offshore Israel
Godol Omri, Gideon Tibor, Uri S. ten Brink, John K. Hall, Gavrielle Groves-Gidney, Gideon Bar-Am, Christian Hubscher, Yizhaq Makovsky
2020, Marine Geology (32) 1166-1193
Understanding continental slope morphological evolution is essential for predicting depositional systems and reservoirs in the adjacent basin. However, present-day slope seafloor-morphology is complicated by shaping processes, which are not readily separable through pure bathymetric analysis. This study aims to explore the utility of bathymetric spectral decomposition in order to separate...
Size matters, but not consistently
Nathan L. Stephenson, Adrian J. Das
2020, Science (365) 962-963
E. Pennisi (“Forest giants are the trees most at risk,” News, 6 September, p. 962) interprets presentations of three studies as suggesting that “for trees, size is not strength, and forest giants are disproportionately vulnerable.” However, this conclusion is not well supported. The observation that lightning is a major cause of...
Context-dependent effects of livestock grazing in deserts of western North America
Kari E. Veblen, Erik A. Beever, David A. Pyke
2020, Book chapter, Disturbance ecology and biological diversity: Scale, context, and nature
This chapter provides a general review of grazing disturbance by large mammalian grazers and the role of ecological context in moderating its effects, with emphasis on North American deserts. It discusses the ecological consequences of cessation of livestock grazing and present a case study from the Mojave Desert, United States...
Pleistocene glacial cycles drove lineage diversification and fusion in the Yosemite toad (Anaxyrus canorus)
Paul A. Maier, Amy G. Vandergast, Steven M Ostoja, Andres Aguilar, Andrew J. Bohonak
2020, Evolution 2476-2496
Species endemic to alpine environments can evolve via steep ecological selection gradients between lowland and upland environments. Additionally, many alpine environments have faced repeated glacial episodes over the past two million years, fracturing these endemics into isolated populations. In this “glacial pulse” model of alpine diversification, cycles of allopatry and...
Push and pull of downstream moving juvenile sea lamprey (Petromyzon marinus) exposed to chemosensory and light cues
Nicholas S. Johnson, Scott M. Miehls, Alexander J. Haro, C. Michael Wagner
2020, Conservation Physiology (7)
Visual and olfactory stimuli induce behavioural responses in fishes when applied independently, but little is known about how simultaneous exposure influences behaviour, especially in downstream migrating fishes. Here, downstream moving juvenile sea lamprey (Petromyzon marinus) were exposed to light and a conspecific chemosensory alarm cue in a flume and movement...
Occupancy Patterns of Breeding American Black Ducks
Anthony J. Roberts, J. Andrew Royle, Paul I. Padding, Patrick K. Devers, Christine Lepage, Daniel Bordage
2020, Journal of Wildlife Management (84) 150-160
Occupancy patterns can assist with the determination of habitat limitation during breeding or wintering periods and can help guide population and habitat management efforts. American black ducks (Anas rubripes; black ducks) are thought to be limited by habitat and food availability during the winter, but breeding sites may also limit...
Reduced species richness of native bees in field margins associated with neonicotinoid concentrations in non-target soils
A.R. Main, Elisabeth B. Webb, K. W. Goyne, D. Mengel
2020, Agriculture, Ecosystems and Environment (287)
Native bees are in decline as many species are sensitive to habitat loss, climate change, and non-target exposure to synthetic pesticides. Recent laboratory and semi-field assessments of pesticide impacts on bees have focused on neonicotinoid insecticides. However, field studies evaluating influences of neonicotinoid seed treatments on native bee communities of...
Population ecology and evaluation of suppression scenarios for an introduced Utah Chub population
Curtis J. Roth, Zachary S. Beard, Jonathan M Flinders, Michael C. Quist
2020, North American Journal of Fisheries Management (40) 133-144
Introduced Utah Chub Gila atraria were first sampled in Henrys Lake, Idaho, in 1993, and their presence in the system is a concern given possible interactions with sport fishes. Our objective was to describe the population dynamics of Utah Chub in Henrys Lake. A total of 362 Utah Chub was sampled via...
Asymptotic population abundance of a two-patch system with asymmetric diffusion
Mengting Fang, Yuanshi Wang, Mingshu Chen, Donald L. DeAngelis
2020, Discrete & Continuous Dynamical Systems-A (40) 3411-3425
This paper considers a two-patch system with asymmetric diffusion rates, in which exploitable resources are included. By using dynamical system theory, we exclude periodic solution in the one-patch subsystem and demonstrate its global dynamics. Then we exhibit uniform persistence of the two-patch system and demonstrate uniqueness of the positive equilibrium,...
Seasonal cycles in hematology and body mass in free-ranging gray wolves (Canis lupus) from northeastern Minnesota, USA
L. David Mech, Deborah A. Buhl
2020, Journal of Wildlife Diseases (56) 179-185
Studies of captive gray wolves (Canis lupus) showed seasonal cycles in hematologic values and female body mass. We used a remotely controlled recapture collar to determine whether nine female and five male free-ranging wolves handled four to 17 times in NE Minnesota, US...
Microsite enhancements for soil stabilization and rapid biocrust colonization in degraded drylands
Stephen E. Fick, Natalie K. Day, Michael C. Duniway, Sean Lawrence Hoy-Skubik, Nichole N. Barger
2020, Restoration Ecology (28) S139-S149
In dryland ecosystems, natural recovery of biological soil crusts (biocrusts) following disturbance may be slow or inhibited, necessitating active restoration practices. While biocrusts can be readily propagated under environmentally controlled conditions, rehabilitation in the field is complicated by environmental stresses which may be particularly acute in...
