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Page 848, results 21176 - 21200

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Assessing angler effort, catch, and harvest and the efficacy of a use-estimation system on a multi-lake fishery in middle Georgia
Hunter J. Roop, Neelam C. Poudyal, Cecil A. Jennings
2018, North American Journal of Fisheries Management (38) 833-841
Creel surveys are valuable tools in recreational fisheries management. However, multiple‐impoundment fisheries of complex spatial structure can complicate survey designs and pose logistical challenges for management agencies. Marben Public Fishing Area in Mansfield, GA is a multi‐impoundment fishery with many access points, and these features prevent or complicate use of...
Integrating authentic scientific research in a conservation course–based undergraduate research experience
Amanda E. Sorensen, Lucia Corral, Jenny M. Dauer, Joseph J. Fontaine
2018, Natural Sciences Education (47)
Course-based undergraduate research experiences (CUREs) have been developed to overcome barriers including students in research. However, there are few examples of CUREs that take place in a conservation and natural resource context with students engaging in field research. Here, we highlight the development of a conservation-focused CURE integrated to a...
Body size and lean mass of brown bears across and within four diverse ecosystems
Grant V. Hilderbrand, David Gustine, Buck A. Mangipane, Kyle Joly, William Leacock, Lindsey S. Mangipane, Joy Erlenbach, Mathew Sorum, Matthew Cameron, Jerrold L. Belant, Troy Cambier
2018, Journal of Zoology (305) 53-62
Variation in body size across populations of brown bears (Ursus arctos) is largely a function of the availability and quality of nutritional resources while plasticity within populations reflects utilized niche width with implications for population resiliency. We assessed skull size, body length, and lean mass of adult female and...
Non-target effects on songbirds from habitat manipulation for Greater Sage-Grouse: Implications for the umbrella species concept
Jason D. Carlisle, Anna D. Chalfoun, Kurt T. Smith, Jeffery L. Beck
2018, The Condor (120) 439-455
The “umbrella species” concept is a conservation strategy in which creating and managing reserve areas to meet the needs of one species is thought to benefit other species indirectly. Broad-scale habitat protections on behalf of an umbrella species are assumed to benefit co-occurring taxa, but targeted management actions to improve...
Precision and relative effectiveness of a purse seine for sampling age-0 river herring in lakes
Matthew T. Devine, Allison H. Roy, Andrew R. Whiteley, Benjamin I. Gahagan, Michael P. Armstrong, Adrian Jordaan
2018, North American Journal of Fisheries Management (38) 650-662
Stock assessments for anadromous river herring, collectively Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis, lack adequate demographic information, particularly with respect to early life stages. Although sampling adult river herring is increasingly common throughout their range, currently no standardized, field‐based, analytical methods exist for estimating juvenile abundance in freshwater lakes. The objective...
Design considerations for estimating survival rates with standing age structures
Rebecca L. Taylor, Mark S. Udevitz
2018, Wildlife Society Bulletin (42) 32-39
Survival rate estimates are critical to understanding the dynamics and status of a population, and they are often inferred from samples of the population’s age structure. A recently developed method uses time series of standing age-structure data with information about population growth rate or fecundity to provide explicit maximum likelihood estimators of age-specific...
Occupancy modeling of Parnassius clodius butterfly populations in Grand Teton National Park, Wyoming
Kimberly E. Szcodronski, Diane M. Debinski, Robert W. Klaver
2018, Journal of Insect Conservation (22) 267-276
Estimating occupancy patterns and identifying vegetation characteristics that influence the presence of butterfly species are essential approaches needed for determining how habitat changes may affect butterfly populations in the future. The montane butterfly species, Parnassius clodius, was investigated to identify patterns of occupancy relating to habitat variables in Grand...
A rapid assessment method to estimate the distribution of juvenile Chinook Salmon in tributary habitats using eDNA and occupancy estimation
A. Matter, Jeffrey A. Falke, J. Andres Lopez, James W. Savereide
2018, North American Journal of Fisheries Management (38) 223-236
Identification and protection of water bodies used by anadromous species are critical in light of increasing threats to fish populations, yet often challenging given budgetary and logistical limitations. Noninvasive, rapid‐assessment, sampling techniques may reduce costs and effort while increasing species detection efficiencies. We used an intrinsic potential (IP) habitat model...
Factors regulating year‐class strength of Silver Carp throughout the Mississippi River basin
Christopher J. Sullivan, Michael J. Weber, Clay Pierce, David H. Wahl, Quinton E. Phelps, Carlos A. Camacho, Robert E. Colombo
2018, Transactions of the American Fisheries Society (147) 541-553
Recruitment of many fish populations is inherently highly variable inter‐annually. However, this variability can be synchronous at broad geographic scales due to fish dispersal and climatic conditions. Herein, we investigated recruitment synchrony of Silver Carp Hypophthalmichthys molitrix across the Mississippi River basin. Year‐class strength (YCS) and synchrony of nine populations (max linear...
Population trends in Vermivora warblers are linked to strong migratory connectivity
Gunnar R. Kramer, David E. Andersen, David A. Buehler, Petra B. Wood, Sean M. Peterson, Justin A. Lehman, Kyle R. Aldinger, Lesley P. Bulluck, Sergio R. Harding, John A. Jones, John P. Loegering, Curtis G. Smalling, Rachel Vallender, Henry M. Streby
2018, Proceedings of the National Academy of Sciences of the United States of America (115) E3192-E3200
Migratory species can experience limiting factors at different locations and during different periods of their annual cycle. In migratory birds, these factors may even occur in different hemispheres. Therefore, identifying the distribution of populations throughout their annual cycle (i.e., migratory connectivity) can reveal the complex ecological and evolutionary relationships that...
A method to quantify and value floodplain sediment and nutrient retention ecosystem services
Kristina G. Hopkins, Gregory E. Noe, Fabiano Franco, Emily Pindilli, Stephanie E. Gordon, Marina J. Metes, Peter R. Claggett, Allen C. Gellis, Cliff R. Hupp, Dianna M. Hogan
2018, Journal of Environmental Management (220) 65-76
Floodplains provide critical ecosystem services to local and downstream communities by retaining floodwaters, sediments, and nutrients. The dynamic nature of floodplains is such that these areas can both accumulate sediment and nutrients through deposition, and export material downstream through erosion. Therefore, estimating floodplain sediment and nutrient retention should consider the...
Identifying diet of a declining prairie grouse using DNA metabarcoding
Daniel S. Sullins, David A. Haukos, Joseph M. Craine, Joseph M. Lautenbach, Samantha G. Robinson, Jonathan D. Lautenbach, John D. Kraft, Reid T. Plumb, J. Reitzer, Brett K. Sandercock, Noah Fierer
2018, The Auk (135) 583-608
Diets during critical brooding and winter periods likely influence the growth of Lesser Prairie-Chicken (Tympanuchus pallidicinctus) populations. During the brooding period, rapidly growing Lesser Prairie-Chicken chicks have high calorie demands and are restricted to foods within immediate surroundings. For adults and juveniles during cold winters, meeting thermoregulatory demands with available...
Ecosystem thresholds, tipping points, and critical transitions
Seth M. Munson, Sasha C. Reed, Josep Penuelas, Nathan G. McDowell, Osvaldo E. Sala
2018, New Phytologist (218) 1315-1317
Abrupt shifts in ecosystems are cause for concern and will likelyintensify under global change (Scheffer et al., 2001). The terms‘thresho lds’, ‘tipping points’, and ‘critical transitions’ have beenused interchangeably to refer to sudden changes in the integrityor state of an ecosystem caused by environmental drivers(Holling, 1973; May, 1977). Threshold-based concepts...
Assessing rockfall susceptibility in steep and overhanging slopes using three-dimensional analysis of failure mechanisms
Battista Matasci, Greg M. Stock, Michael Jaboyedoff, Dario Carrea, Brian D. Collins, Antoine Guerin, G. Matasci, L. Ravanel
2018, Landslides (15) 859-878
Rockfalls strongly influence the evolution of steep rocky landscapes and represent a significant hazard in mountainous areas. Defining the most probable future rockfall source areas is of primary importance for both geomorphological investigations and hazard assessment. Thus, a need exists to understand which areas of a steep cliff are more...
Estimating distribution and connectivity of recolonizing American marten in the northeastern United States using expert elicitation techniques
C.M. Aylward, J.D. Murdoch, Therese M. Donovan, C.W. Kilpatrick, C. Bernier, J. Katz
2018, Animal Conservation (21) 483-495
The American marten Martes americana is a species of conservation concern in the northeastern United States due to widespread declines from over‐harvesting and habitat loss. Little information exists on current marten distribution and how landscape characteristics shape patterns of occupancy across the region, which could help develop effective recovery strategies. The rarity...
Effects of turbidity, sediment, and polyacrylamide on native freshwater mussels
Sean B. Buczek, W. Gregory Cope, Richard A. McLaughlin, Thomas J. Kwak
2018, Journal of the American Water Resources Association (54) 631-643
Turbidity is a ubiquitous pollutant adversely affecting water quality and aquatic life in waterways globally. Anionic polyacrylamide (PAM) is widely used as an effective chemical flocculent to reduce suspended sediment (SS) and turbidity. However, no information exists on the toxicity of PAM‐flocculated sediments to imperiled, but ecologically important, freshwater mussels...
Imidacloprid sorption and transport in cropland, grass buffer and riparian buffer soils
Laura E. Satkowski, Keith W. Goyne, Stephen H. Anderson, Robert N. Lerch, Craig R. Allen, Daniel D. Snow
2018, Vadose Zone Journal (17) 1-12
An understanding of neonicotinoid sorption and transport in soil is critical for determining and mitigating environmental risk associated with the most widely used class of insecticides. The objective of this study was to evaluate mobility and transport of the neonicotinoid imidacloprid (ICD) in soils collected from cropland, grass vegetative buffer...
Crowding affects health, growth, and behavior in headstart pens for Agassiz's desert tortoise
Jeremy S. Mack, Heather E. Schneider, Kristin H. Berry
2018, Chelonian Conservation and Biology (17) 14-26
Worldwide, scientists have headstarted threatened and endangered reptiles to augment depleted populations. Not all efforts have been successful. For the threatened Agassiz's desert tortoise (Gopherus agassizii), one challenge to recovery is poor recruitment of juveniles into adult populations, and this is being addressed through headstart programs. We evaluated 8 cohorts...
Precision of four otolith techniques for estimating age of white perch from a thermally altered reservoir
Richard A. Snow, Michael J. Porta, James M. Long
2018, North American Journal of Fisheries Management (38) 725-733
The White Perch Morone americana is an invasive species in many Midwestern states and is widely distributed in reservoir systems, yet little is known about the species' age structure and population dynamics. White Perch were first observed in Sooner Reservoir, a thermally altered cooling reservoir in Oklahoma, by the Oklahoma Department of...
Shoal bass hybridization in the Chattahoochee River Basin near Atlanta, Georgia
Andrew T. Taylor, Michael D. Tringali, Patrick M. O’Rourke, James M. Long
2018, Journals of the Southeastern Association of Fish and Wildlife Agencies (5) 1-9
The shoal bass (Micropterus cataractae) is a sportfish endemic to the Apalachicola-Chattahoochee-Flint Basin of the southeastern United States. Introgression with several non-native congeners poses a pertinent threat to shoal bass conservation, particularly in the altered habitats of the Chattahoochee River. Our primary objective was to characterize hybridization in shoal bass...
Ecological neighborhoods as a framework for umbrella species selection
Erica F. Stuber, Joseph J. Fontaine
2018, Biological Conservation (223) 112-119
Umbrella species are typically chosen because they are expected to confer protection for other species assumed to have similar ecological requirements. Despite its popularity and substantial history, the value of the umbrella species concept has come into question because umbrella species chosen using heuristic methods, such as body or home...
Fall and winter microhabitat use and suitability for spring chinook salmon parr in a U.S. Pacific Northwest River
Scott D. Favrot, Brian C. Jonasson, James T. Peterson
2018, Transactions of the American Fisheries Society (147) 151-170
Habitat degradation has been implicated as a primary threat to Pacific salmon Oncorhynchus spp. Habitat restoration and conservation are key toward stemming population declines; however, winter microhabitat use and suitability knowledge are lacking for small juvenile salmonids. Our objective was to characterize microhabitat use and suitability for spring Chinook Salmon Oncorhynchus tshawytscha parr during...
Effects of summer air exposure on the survival of caught-and-released salmonids
Curtis J. Roth, Daniel J. Schill, Michael C. Quist, Brett High
2018, North American Journal of Fisheries Management (38) 886-895
Despite the success of catch‐and‐release regulations, exposing fish to air during release has emerged as a growing concern over the past two decades. We evaluated the effect of air exposure during midsummer on survival of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri, Bull Trout Salvelinus confluentus, and Rainbow Trout O. mykiss exposed to catch‐and‐release angling....
A guide to Bayesian model checking for ecologists
Paul B. Conn, Devin S. Johnson, Perry J. Williams, Sharon R. Melin, Mevin Hooten
2018, Ecological Monographs (88) 526-542
Checking that models adequately represent data is an essential component of applied statistical inference. Ecologists increasingly use hierarchical Bayesian statistical models in their research. The appeal of this modeling paradigm is undeniable, as researchers can build and fit models that embody complex ecological processes while simultaneously accounting for observation error....
Probabilistic measures of climate change vulnerability, adaptation action benefits, and related uncertainty from maximum temperature metric selection
Jefferson T. DeWeber, Tyler Wagner
2018, Global Change Biology (24) 2735-2748
Predictions of the projected changes in species distributions and potential adaptation action benefits can help guide conservation actions. There is substantial uncertainty in projecting species distributions into an unknown future, however, which can undermine confidence in predictions or misdirect conservation actions if not properly considered. Recent studies have shown that...