Anna Chalfoun, PhD
Assistant Unit Leader - Wyoming Cooperative Fish and Wildlife Research Unit
Anna joined the faculty at the University of Wyoming as a Research Scientist in 2008, and was hired as the Assistant Unit Leader for Wildlife at the Wyoming Unit in 2011. Anna ’s work has focused on understanding the mechanisms underlying habitat selection at multiple spatial scales, the contexts under which habitat choices are adaptive or maladative, nest predation dynamics, life history strategies including parental care behaviors, and the influence of anthropogenic habitat change on non-game wildlife. Anna and her graduate students conduct research on songbirds, raptors, small mammals, and herpetofauna in a wide variety of habitats in Wyoming and beyond. The common threads woven throughout the lab's projects include wildlife habitat relationships and the influence of human-induced habitat changes such as loss, fragmentation and degradation on sensitive species. Projects in the Chalfoun lab have included the effects of energy development, roads, and a changing climate. Anna is the coChair of the Conservation Committee for the American Ornithological Society.
Anna holds a BA degree in Biology from Smith College, an MS in Wildlife Biology and Conservation Biology from the University of Missouri, and a PhD in Wildlife Biology from the Montana CRU at the University of Montana.
Education and Certifications
Ph D University of Montana 2006
MS University of Missouri 2000
BA Smith College 1995
Science and Products
Filter Total Items: 50
Experimental reduction of a primary nest predator fails to decrease nest predation rates of sagebrush songbirds
Brewer’s Sparrow (Spizella breweri), Sagebrush Sparrow (Artemisiospiza nevadensis), and Sage Thrasher (Oreoscoptus montanus)—during May to August 2019 in western Wyoming, USA, to assess whether nest predation risk was additive or compensatory, and whether nest predator removal could comprise a potentially effective management tool. Deer mouse removal did not affect the daily nest...
Authors
Ashleigh M. Rhea, Anna D. Chalfoun
Beyond overlap: Considering habitat preference and fitness outcomes in the umbrella species concept
Umbrella species and other surrogate species approaches to conservation provide an appealing framework to extend the reach of conservation efforts beyond single species. For the umbrella species concept to be effective, populations of multiple species of concern must persist in areas protected on behalf of the umbrella species. Most assessments of the concept, however, focus exclusively...
Authors
Jay Carlisle, K. T. Smith, J. Warren Beck, M. A. Murphy, Anna D. Chalfoun
Congruence among multiple indices of habitat preference for species facing human-induced rapid environmental change: A case study using the Brewer's sparrow
Accurate evaluations of habitat preference are key to understanding optimal conditions for wildlife survival and reproduction. Habitat selection, however, usually is evaluated using a single index of preference, and congruence among multiple, relevant indices of preference is examined rarely.We assessed the concordance between patterns of habitat preference using three different indices...
Authors
Max Carlin, Anna D. Chalfoun
Wildfire influences individual growth and breeding dispersal, but not survival and recruitment in a montane amphibian
Global wildfire regimes are changing rapidly, with widespread increases in the size, frequency, duration, and severity of wildfires. Whereas the effects of wildfire on ecological state variables such as occupancy, abundance, and species diversity are relatively well documented, changes in population vital rates (e.g., survival, recruitment) and individual responses (e.g., growth...
Authors
Gabriel M. Barrile, Anna D. Chalfoun, Wendy A. Estes-Zumpf, Annika W. Walters
Intrabrood variation in nestling mass among three sagebrush-associated songbirds
The young of some altricial bird species hatch asynchronously, which can lead to considerable size differences among siblings. Nestling traits such as body mass, moreover, can carry over and influence post-fledging survival. Despite the potential importance of nestling mass for reproductive outcomes, however, variation in nestling mass and relationships with brood size has been described...
Authors
Ashleigh M. Rhea, Jason D. Carlisle, Anna D. Chalfoun
Taming the temperature: Sagebrush songbirds modulate microclimate via nest-site selection
Understanding species’ responses to temperature via behavior, and the factors affecting the extent of behavioral responses, is a critical and timely endeavor given the rapid pace at which the climate is changing. The young of altricial songbirds are particularly sensitive to temperature, and parents may modulate temperatures at nests via selection of nest sites, albeit to a largely...
Authors
Tayler M. Scherr, Anna D. Chalfoun
Stage-specific environmental correlates of reproductive success in Boreal Toads (Anaxyrus boreas boreas)
Compensatory recruitment can facilitate the persistence of populations experiencing high adult mortality. Because early life-stages of many taxa, including amphibians, are difficult to mark and recapture, sources of variation in survival at these stages often are unknown, which creates barriers to improving in situ recruitment rates. We leveraged count data and open N-mixture models to...
Authors
Gabriel M. Barrile, Annika W. Walters, Anna D. Chalfoun
Site fidelity as a maladaptive behavior in the Anthropocene
Site fidelity, or the behavior of returning to previously visited locations, has been observed across taxa and ecosystems. By developing familiarity with a particular location, site fidelity provides a range of benefits and is advantageous in stable or predictable environments. However, the Anthropocene is characterized by rates of environmental change that outpace the evolutionary...
Authors
Jerod A. Merkle, Briana L. Abrahms, Jonathan B. Armstrong, Hall Sawyer, Daniel P. Costa, Anna D. Chalfoun
Livestock grazing, climatic variation, and breeding phenology jointly shape disease dynamics and survival in a wild amphibian
Wildlife responses to infectious disease can be influenced by environmental stressors that alter host-pathogen dynamics. We investigated how livestock grazing, climatic variation, and breeding phenology influence disease prevalence and annual survival in boreal toad (Anaxyrus boreas boreas) populations challenged with Batrachochytrium dendrobatidis (Bd), a fungal pathogen implicated in...
Authors
Gabriel M. Barrile, Annika W. Walters, Anna D. Chalfoun
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
The Wyoming Landscape Conservation Initiative (WLCI) was established in 2007 as a collaborative interagency partnership to develop and implement science-based conservation actions. During the past 11 years, partners from U.S. Geological Survey (USGS), State and Federal land management agencies, universities, and the public have collaborated to implement a long-term (more than 10 years)...
Authors
Patrick J. Anderson, Cameron L. Aldridge, Jason S. Alexander, Timothy J. Assal, Steven Aulenbach, Zachary H. Bowen, Anna D. Chalfoun, Geneva W. Chong, Holly Copeland, David R. Edmunds, Stephen S. Germaine, Tabitha A. Graves, Julie A. Heinrichs, Collin Homer, Christopher Huber, Aaron N. Johnston, Matthew Kauffman, Daniel J. Manier, Ryan R. McShane, Cheryl Miller, Kirk A. Miller, Adrian Pierre-Frederic Monroe, Michael S. O'Donnell, Anna C. Ortega, Annika W. Walters, Daniel J. Wieferich, Teal B. Wyckoff, Linda Zeigenfuss
Responses of vertebrate wildlife to oil and natural gas development: Patterns and frontiers
Purpose of ReviewAnthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’...
Authors
Anna D. Chalfoun
Informed breeding dispersal following stochastic changes to patch quality in a pond-breeding amphibian
The unidirectional movement of animals between breeding patches (i.e. breeding dispersal) has profound implications for the ecological and evolutionary dynamics of spatially structured populations. In spatiotemporally variable environments, individuals are expected to adjust their dispersal decisions according to information gathered on the environmental and/or social cues that reflect...
Authors
Gabriel M. Barrile, Annika W. Walters, Matthew Webster, Anna D. Chalfoun
Science and Products
Filter Total Items: 50
Experimental reduction of a primary nest predator fails to decrease nest predation rates of sagebrush songbirds
Brewer’s Sparrow (Spizella breweri), Sagebrush Sparrow (Artemisiospiza nevadensis), and Sage Thrasher (Oreoscoptus montanus)—during May to August 2019 in western Wyoming, USA, to assess whether nest predation risk was additive or compensatory, and whether nest predator removal could comprise a potentially effective management tool. Deer mouse removal did not affect the daily nest...
Authors
Ashleigh M. Rhea, Anna D. Chalfoun
Beyond overlap: Considering habitat preference and fitness outcomes in the umbrella species concept
Umbrella species and other surrogate species approaches to conservation provide an appealing framework to extend the reach of conservation efforts beyond single species. For the umbrella species concept to be effective, populations of multiple species of concern must persist in areas protected on behalf of the umbrella species. Most assessments of the concept, however, focus exclusively...
Authors
Jay Carlisle, K. T. Smith, J. Warren Beck, M. A. Murphy, Anna D. Chalfoun
Congruence among multiple indices of habitat preference for species facing human-induced rapid environmental change: A case study using the Brewer's sparrow
Accurate evaluations of habitat preference are key to understanding optimal conditions for wildlife survival and reproduction. Habitat selection, however, usually is evaluated using a single index of preference, and congruence among multiple, relevant indices of preference is examined rarely.We assessed the concordance between patterns of habitat preference using three different indices...
Authors
Max Carlin, Anna D. Chalfoun
Wildfire influences individual growth and breeding dispersal, but not survival and recruitment in a montane amphibian
Global wildfire regimes are changing rapidly, with widespread increases in the size, frequency, duration, and severity of wildfires. Whereas the effects of wildfire on ecological state variables such as occupancy, abundance, and species diversity are relatively well documented, changes in population vital rates (e.g., survival, recruitment) and individual responses (e.g., growth...
Authors
Gabriel M. Barrile, Anna D. Chalfoun, Wendy A. Estes-Zumpf, Annika W. Walters
Intrabrood variation in nestling mass among three sagebrush-associated songbirds
The young of some altricial bird species hatch asynchronously, which can lead to considerable size differences among siblings. Nestling traits such as body mass, moreover, can carry over and influence post-fledging survival. Despite the potential importance of nestling mass for reproductive outcomes, however, variation in nestling mass and relationships with brood size has been described...
Authors
Ashleigh M. Rhea, Jason D. Carlisle, Anna D. Chalfoun
Taming the temperature: Sagebrush songbirds modulate microclimate via nest-site selection
Understanding species’ responses to temperature via behavior, and the factors affecting the extent of behavioral responses, is a critical and timely endeavor given the rapid pace at which the climate is changing. The young of altricial songbirds are particularly sensitive to temperature, and parents may modulate temperatures at nests via selection of nest sites, albeit to a largely...
Authors
Tayler M. Scherr, Anna D. Chalfoun
Stage-specific environmental correlates of reproductive success in Boreal Toads (Anaxyrus boreas boreas)
Compensatory recruitment can facilitate the persistence of populations experiencing high adult mortality. Because early life-stages of many taxa, including amphibians, are difficult to mark and recapture, sources of variation in survival at these stages often are unknown, which creates barriers to improving in situ recruitment rates. We leveraged count data and open N-mixture models to...
Authors
Gabriel M. Barrile, Annika W. Walters, Anna D. Chalfoun
Site fidelity as a maladaptive behavior in the Anthropocene
Site fidelity, or the behavior of returning to previously visited locations, has been observed across taxa and ecosystems. By developing familiarity with a particular location, site fidelity provides a range of benefits and is advantageous in stable or predictable environments. However, the Anthropocene is characterized by rates of environmental change that outpace the evolutionary...
Authors
Jerod A. Merkle, Briana L. Abrahms, Jonathan B. Armstrong, Hall Sawyer, Daniel P. Costa, Anna D. Chalfoun
Livestock grazing, climatic variation, and breeding phenology jointly shape disease dynamics and survival in a wild amphibian
Wildlife responses to infectious disease can be influenced by environmental stressors that alter host-pathogen dynamics. We investigated how livestock grazing, climatic variation, and breeding phenology influence disease prevalence and annual survival in boreal toad (Anaxyrus boreas boreas) populations challenged with Batrachochytrium dendrobatidis (Bd), a fungal pathogen implicated in...
Authors
Gabriel M. Barrile, Annika W. Walters, Anna D. Chalfoun
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2018 annual report
The Wyoming Landscape Conservation Initiative (WLCI) was established in 2007 as a collaborative interagency partnership to develop and implement science-based conservation actions. During the past 11 years, partners from U.S. Geological Survey (USGS), State and Federal land management agencies, universities, and the public have collaborated to implement a long-term (more than 10 years)...
Authors
Patrick J. Anderson, Cameron L. Aldridge, Jason S. Alexander, Timothy J. Assal, Steven Aulenbach, Zachary H. Bowen, Anna D. Chalfoun, Geneva W. Chong, Holly Copeland, David R. Edmunds, Stephen S. Germaine, Tabitha A. Graves, Julie A. Heinrichs, Collin Homer, Christopher Huber, Aaron N. Johnston, Matthew Kauffman, Daniel J. Manier, Ryan R. McShane, Cheryl Miller, Kirk A. Miller, Adrian Pierre-Frederic Monroe, Michael S. O'Donnell, Anna C. Ortega, Annika W. Walters, Daniel J. Wieferich, Teal B. Wyckoff, Linda Zeigenfuss
Responses of vertebrate wildlife to oil and natural gas development: Patterns and frontiers
Purpose of ReviewAnthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’...
Authors
Anna D. Chalfoun
Informed breeding dispersal following stochastic changes to patch quality in a pond-breeding amphibian
The unidirectional movement of animals between breeding patches (i.e. breeding dispersal) has profound implications for the ecological and evolutionary dynamics of spatially structured populations. In spatiotemporally variable environments, individuals are expected to adjust their dispersal decisions according to information gathered on the environmental and/or social cues that reflect...
Authors
Gabriel M. Barrile, Annika W. Walters, Matthew Webster, Anna D. Chalfoun