Evan Grant, Ph.D.
Evan Grant the principle investigator of the US Geological Survey’s Amphibian Research and Monitoring Initiative (ARMI), northeast region.
Evan's research focuses on questions relating to amphibian populations, specifically with respect to their landscape-scale ecology. Evan also uses decision science to aid resource managers.
Education:
- PhD, 2009, University of Maryland College Park, Program of Marine, Estuarine and Environmental Sciences and Department of Entomology
- BS, 2001, Cornell University, Natural Resources, with Distinction in Research
ResearcherID: N-5160-2014
Research Gate profile: http://www.researchgate.net/profile/Evan_Grant2
Science and Products
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Modeling structured population dynamics using data from unmarked individuals
The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark–recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters a
Authors
Evan H. Campbell Grant, Elise Zipkin, James T. Thorson, Kevin See, Heather J. Lynch, Yoichiro Kanno, Richard Chandler, Benjamin H. Letcher, J. Andrew Royle
Relaxing the closure assumption in single-season occupancy models: staggered arrival and departure times
Occupancy statistical models that account for imperfect detection have proved very useful in several areas of ecology, including species distribution and spatial dynamics, disease ecology, and ecological responses to climate change. These models are based on the collection of multiple samples at each of a number of sites within a given season, during which it is assumed the species is either absen
Authors
William L. Kendall, James E. Hines, James D. Nichols, Evan H. Campbell Grant
Trends in amphibian occupancy in the United States
Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphi
Authors
M. J. Adams, David A.W. Miller, Erin Muths, Paul Stephen Corn, Evan H. Campbell Grant, Larissa L. Bailey, Gary M. Fellers, Robert N. Fisher, Walter J. Sadinski, Hardin Waddle, Susan C. Walls
Presence-only modeling using MAXENT: when can we trust the inferences?
1. Recently, interest in species distribution modelling has increased following the development of new methods for the analysis of presence-only data and the deployment of these methods in user-friendly and powerful computer programs. However, reliable inference from these powerful tools requires that several assumptions be met, including the assumptions that observed presences are the consequence
Authors
Charles B. Yackulic, Richard Chandler, Elise F. Zipkin, J. Andrew Royle, James D. Nichols, Evan H. Campbell Grant, Sophie Veran
The state of amphibians in the United States
More than 25 years ago, scientists began to identify unexplained declines in amphibian populations around the world. Much has been learned since then, but amphibian declines have not abated and the interactions among the various threats to amphibians are not clear. Amphibian decline is a problem of local, national, and international scope that can affect ecosystem function, biodiversity, and comme
Authors
E. Muths, M.J. Adams, E.H.C. Grant, D. Miller, P. S. Corn, L.C. Ball
Evaluating the predictive abilities of community occupancy models using AUC while accounting for imperfect detection
The ability to accurately predict patterns of species' occurrences is fundamental to the successful management of animal communities. To determine optimal management strategies, it is essential to understand species-habitat relationships and how species habitat use is related to natural or human-induced environmental changes. Using five years of monitoring data in the Chesapeake and Ohio Canal N
Authors
Elise F. Zipkin, Evan H. Campbell Grant, William F. Fagan
Experimental investigation of false positive errors in auditory species occurrence surveys
False positive errors are a significant component of many ecological data sets, which in combination with false negative errors, can lead to severe biases in conclusions about ecological systems. We present results of a field experiment where observers recorded observations for known combinations of electronically broadcast calling anurans under conditions mimicking field surveys to determine spec
Authors
David A.W. Miller, Linda A. Weir, Brett T. McClintock, Evan H. Campbell Grant, Larissa L. Bailey, Theodore R. Simons
The U.S. Geological Survey Amphibian Research and Monitoring Initiative-2011 Annual Update
Welcome to the inaugural issue of ARMI's Annual Update. This update provides highlights and significant milestones of this innovative program. ARMI is uniquely qualified to provide research and monitoring results that are scalable from local to national levels, and are useful to resource managers. ARMI has produced nearly 400 peer-reviewed publications, including 18 in 2011. Some of those publicat
Authors
M.J. Adams, E. Muths, E.H.C. Grant, David A. Miller, J.H. Waddle, L.C. Ball
Interbasin water transfer, riverine connectivity, and spatial controls on fish biodiversity
Background Large-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fis
Authors
Evan H. Campbell Grant, Heather J. Lynch, Rachata Muneepeerakul, Arunachalam Muthukumarasamy, Ignacio Rodríguez-Iturbe, William F. Fagan
Structural complexity, movement bias, and metapopulation extinction risk in dendritic ecological networks
Spatial complexity in metacommunities can be separated into 3 main components: size (i.e., number of habitat patches), spatial arrangement of habitat patches (network topology), and diversity of habitat patch types. Much attention has been paid to lattice-type networks, such as patch-based metapopulations, but interest in understanding ecological networks of alternative geometries is building. Den
Authors
Evan H. Campbell Grant
Landscape matrix mediates occupancy dynamics of Neotropical avian insectivores
In addition to patch‐level attributes (i.e., area and isolation), the nature of land cover between habitat patches (the matrix) may drive colonization and extinction dynamics in fragmented landscapes. Despite a long‐standing recognition of matrix effects in fragmented systems, an understanding of the relative impacts of different types of land cover on patterns and dynamics of species occurrence r
Authors
Christina M. Kennedy, Evan H. Campbell Grant, Maile C. Neel, William F. Fagan, Peter P. Marra
How restructuring river connectivity changes freshwater fish biodiversity and biogeography
Interbasin water transfer projects, in which river connectivity is restructured via man-made canals, are an increasingly popular solution to address the spatial mismatch between supply and demand of fresh water. However, the ecological consequences of such restructuring remain largely unexplored, and there are no general theoretical guidelines from which to derive these expectations. River systems
Authors
Heather L. Lynch, Evan H. Campbell Grant, Rachata Muneepeerakul, Muthukumarasamy Arunachalam, Ignacio Rodriguez-Iturbe, William F. Fagan
Science and Products
Filter Total Items: 20
Filter Total Items: 19
No Result Found
Filter Total Items: 137
Modeling structured population dynamics using data from unmarked individuals
The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark–recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters a
Authors
Evan H. Campbell Grant, Elise Zipkin, James T. Thorson, Kevin See, Heather J. Lynch, Yoichiro Kanno, Richard Chandler, Benjamin H. Letcher, J. Andrew Royle
Relaxing the closure assumption in single-season occupancy models: staggered arrival and departure times
Occupancy statistical models that account for imperfect detection have proved very useful in several areas of ecology, including species distribution and spatial dynamics, disease ecology, and ecological responses to climate change. These models are based on the collection of multiple samples at each of a number of sites within a given season, during which it is assumed the species is either absen
Authors
William L. Kendall, James E. Hines, James D. Nichols, Evan H. Campbell Grant
Trends in amphibian occupancy in the United States
Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphi
Authors
M. J. Adams, David A.W. Miller, Erin Muths, Paul Stephen Corn, Evan H. Campbell Grant, Larissa L. Bailey, Gary M. Fellers, Robert N. Fisher, Walter J. Sadinski, Hardin Waddle, Susan C. Walls
Presence-only modeling using MAXENT: when can we trust the inferences?
1. Recently, interest in species distribution modelling has increased following the development of new methods for the analysis of presence-only data and the deployment of these methods in user-friendly and powerful computer programs. However, reliable inference from these powerful tools requires that several assumptions be met, including the assumptions that observed presences are the consequence
Authors
Charles B. Yackulic, Richard Chandler, Elise F. Zipkin, J. Andrew Royle, James D. Nichols, Evan H. Campbell Grant, Sophie Veran
The state of amphibians in the United States
More than 25 years ago, scientists began to identify unexplained declines in amphibian populations around the world. Much has been learned since then, but amphibian declines have not abated and the interactions among the various threats to amphibians are not clear. Amphibian decline is a problem of local, national, and international scope that can affect ecosystem function, biodiversity, and comme
Authors
E. Muths, M.J. Adams, E.H.C. Grant, D. Miller, P. S. Corn, L.C. Ball
Evaluating the predictive abilities of community occupancy models using AUC while accounting for imperfect detection
The ability to accurately predict patterns of species' occurrences is fundamental to the successful management of animal communities. To determine optimal management strategies, it is essential to understand species-habitat relationships and how species habitat use is related to natural or human-induced environmental changes. Using five years of monitoring data in the Chesapeake and Ohio Canal N
Authors
Elise F. Zipkin, Evan H. Campbell Grant, William F. Fagan
Experimental investigation of false positive errors in auditory species occurrence surveys
False positive errors are a significant component of many ecological data sets, which in combination with false negative errors, can lead to severe biases in conclusions about ecological systems. We present results of a field experiment where observers recorded observations for known combinations of electronically broadcast calling anurans under conditions mimicking field surveys to determine spec
Authors
David A.W. Miller, Linda A. Weir, Brett T. McClintock, Evan H. Campbell Grant, Larissa L. Bailey, Theodore R. Simons
The U.S. Geological Survey Amphibian Research and Monitoring Initiative-2011 Annual Update
Welcome to the inaugural issue of ARMI's Annual Update. This update provides highlights and significant milestones of this innovative program. ARMI is uniquely qualified to provide research and monitoring results that are scalable from local to national levels, and are useful to resource managers. ARMI has produced nearly 400 peer-reviewed publications, including 18 in 2011. Some of those publicat
Authors
M.J. Adams, E. Muths, E.H.C. Grant, David A. Miller, J.H. Waddle, L.C. Ball
Interbasin water transfer, riverine connectivity, and spatial controls on fish biodiversity
Background Large-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fis
Authors
Evan H. Campbell Grant, Heather J. Lynch, Rachata Muneepeerakul, Arunachalam Muthukumarasamy, Ignacio Rodríguez-Iturbe, William F. Fagan
Structural complexity, movement bias, and metapopulation extinction risk in dendritic ecological networks
Spatial complexity in metacommunities can be separated into 3 main components: size (i.e., number of habitat patches), spatial arrangement of habitat patches (network topology), and diversity of habitat patch types. Much attention has been paid to lattice-type networks, such as patch-based metapopulations, but interest in understanding ecological networks of alternative geometries is building. Den
Authors
Evan H. Campbell Grant
Landscape matrix mediates occupancy dynamics of Neotropical avian insectivores
In addition to patch‐level attributes (i.e., area and isolation), the nature of land cover between habitat patches (the matrix) may drive colonization and extinction dynamics in fragmented landscapes. Despite a long‐standing recognition of matrix effects in fragmented systems, an understanding of the relative impacts of different types of land cover on patterns and dynamics of species occurrence r
Authors
Christina M. Kennedy, Evan H. Campbell Grant, Maile C. Neel, William F. Fagan, Peter P. Marra
How restructuring river connectivity changes freshwater fish biodiversity and biogeography
Interbasin water transfer projects, in which river connectivity is restructured via man-made canals, are an increasingly popular solution to address the spatial mismatch between supply and demand of fresh water. However, the ecological consequences of such restructuring remain largely unexplored, and there are no general theoretical guidelines from which to derive these expectations. River systems
Authors
Heather L. Lynch, Evan H. Campbell Grant, Rachata Muneepeerakul, Muthukumarasamy Arunachalam, Ignacio Rodriguez-Iturbe, William F. Fagan