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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16783

A review and synthesis of recreation ecology research supporting carrying capacity and visitor use management decisionmaking

Resource and experiential impacts associated with visitation to wilderness and other similar backcountry settings have long been addressed by land managers under the context of “carrying capacity” decisionmaking. Determining a maximum level of allowable use, below which high-quality resource and experiential conditions would be sustained, was an early focus in the 1960s and 1970s. However, decades
Authors
Jeffrey L. Marion

A review and synthesis of recreation ecology research findings on visitor impacts to wilderness and protected natural areas

The 50th anniversary of the US Wilderness Act of 1964 presents a worthy opportunity to review our collective knowledge on how recreation visitation affects wilderness and protected natural area resources. Studies of recreation impacts, examined within the recreation ecology field of study, have spanned 80 years and generated more than 1,200 citations. This article examines the recreation ecology l
Authors
Jeffrey L. Marion, Yu-Fai Leung, Holly Eagleston, Kaitlin Burroughs

Analysis of hydrologic and geochemical time-series data at James Cave, Virginia: Implications for epikarst influence on recharge in Appalachian karst aquifers

The epikarst, which consists of highly weathered rock in the upper vadose zone of exposed karst systems, plays a critical role in determining the hydrologic and geochemical characteristics of recharge to an underlying karst aquifer. This study utilized time series (2007–2014) of hydrologic and geochemical data of drip water collected within James Cave, Virginia, to examine the influence of epikars
Authors
Sarah D. Eagle, William Orndorff, Benjamin F. Schwartz, Daniel H. Doctor, Jonathan D. Gerst, Madeline E. Schreiber

Cross-seasonal effects on waterfowl productivity: Implications under climate change

Previous efforts to relate winter-ground precipitation to subsequent reproductive success as measured by the ratio of juveniles to adults in the autumn failed to account for increased vulnerability of juvenile ducks to hunting and uncertainty in the estimated age ratio. Neglecting increased juvenile vulnerability will positively bias the mean productivity estimate, and neglecting increased vulnera
Authors
Erik E. Osnas, Qing Zhao, Michael C. Runge, G Scott Boomer

Adaptive management for improving species conservation across the captive-wild spectrum

Conservation of endangered species increasingly envisages complex strategies that integrate captive and wild management actions. Management decisions in this context must be made in the face of uncertainty, often with limited capacity to collect information. Adaptive management (AM) combines management and monitoring, with the aim of updating knowledge and improving decision-making over time. We p
Authors
Stefano Canessa, Gurutzeta Guillera-Arroita, José J. Lahoz-Monfort, Darren M Southwell, Doug P. Armstrong, Iadine Chadès, Robert C Lacy, Sarah J. Converse

Urban base flow with low impact development

A novel form of urbanization, low impact development (LID), aims to engineer systems that replicate natural hydrologic functioning, in part by infiltrating stormwater close to the impervious surfaces that generate it. We sought to statistically evaluate changes in a base flow regime because of urbanization with LID, specifically changes in base flow magnitude, seasonality, and rate of change. We u
Authors
Aditi Bhaskar, Dianna M. Hogan, Stacey A. Archfield

The road to NHDPlus — Advancements in digital stream networks and associated catchments

A progression of advancements in Geographic Information Systems techniques for hydrologic network and associated catchment delineation has led to the production of the National Hydrography Dataset Plus (NHDPlus). NHDPlus is a digital stream network for hydrologic modeling with catchments and a suite of related geospatial data. Digital stream networks with associated catchments provide a geospatial
Authors
Richard B. Moore, Thomas A. Dewald

Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants

Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)—tagged chimeric molecule of glucocorticoid receptor (GR) and the thyr
Authors
Diana A. Stavreva, Lyuba Varticovski, Ludmila Levkova, Anuja A. George, Luke Davis, Gianluca Pegoraro, Vicki S. Blazer, Luke R. Iwanowicz, Gordon L. Hager

An exploratory assessment of thiamine status in western Alaska Chinook salmon (Oncorhynchus tshawytscha)

This study was conducted to investigate the thiamine status of Chinook salmon Oncorhynchus tshawytscha. Egg thiamine levels in Yukon and Kuskokwim River Chinook were examined in 2001 and 2012. Muscle and liver thiamine in Chinook, coho O. kisutch, chum O. keta, and pink O. gorbuscha salmon were measured in northern Bering Sea juveniles and the percentage of the diet containing thiaminase, an enzym
Authors
Dale C. Honeyfield, James M. Murphy, Katherine G. Howard, Wesley W. Strasburger, A.C. Matz

Osmoregulatory physiology and rapid evolution of salinity tolerance in threespine stickleback recently introduced to fresh water

Background: Post-Pleistocene diversification of threespine stickleback in fresh water offers a valuable opportunity to study how changes in environmental salinity shape physiological evolution in fish. In Alaska, the presence of both ancestral oceanic populations and derived landlocked populations, including recent lake introductions, allows us to examine rates and direction of evolution of osmore
Authors
Jeffrey N Divino, Michelle Y. Monette, Stephen D. McCormick, Paul H. Yancey, Kyle G. Flannery, Michael A. Bell, Jennifer L. Rollins, Frank A. von Hippel, Eric T. Schultz

Tracking domestic ducks: A novel approach for documenting poultry market chains in the context of avian influenza transmission

Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian influenza (HPAI) are not well understood, but the trade of live poultry is suspected to be a major pathway. Although market chains of live bird trade have been studied through indirect means including interviews and questionnaires, direct methods have not been used to identify movements of individual p
Authors
Chang-Yong Choi, John Y. Takekawa, Yue Xiong, Martin Wikelski, George Heine, Diann J. Prosser, Scott H. Newman, John Edwards, Fusheng Guo, Xiangming Xiao

Variability of bed drag on cohesive beds under wave action

Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom
Authors
Ilgar Safak