James Nichols, Ph.D.
Dr. Jim Nichols conducts research on animal population dynamics and management
Recent Accomplishments
Education
- B.S. Wake Forest University, Biology, 1971
- M.S. Louisiana State University, Wildlife Management, 1973
- Ph.D. Michigan State University, Wildlife Ecology, 1976
Professional Studies/Experience
- Adaptive management and assessment of habitat changes on migratory birds
- Development of models of mallard population dynamics for adaptive harvest management
- Development of methods to estimate parameters associated with animal population dynamics
- Statistical methods for species richness estimation
- Technical Assistance -Tiger Monitoring and Population Research
- Development of methods for estimating patch occupancy and patch-dynamic parameters from detection-nondetection survey data
- Development of methods to estimate species richness and community-dynamic parameters from species list data
Mentorship/Outreach
Professional societies/affiliations/committees/editorial boardsScientific/Oral Presentations, Abstracts
Honors, awards, recognition, elected offices
- 2005 - U.S. Presidential Rank Award (Meritorious Senior Professional)
- 2004 - U.S. Geological Survey Meritorious Service Award
- 2004 - IFAS Scholar Award, University of Florida
- 1998 - Promoted to Senior Scientist, U.S. Geological Survey
- 1991 - The George W. Snedecor Award of the American Statistical Association
- 1991 - The Wildlife Society's Wildlife Publication Award for Monograph
- 1984 - Southeastern Section of the Wildlife Society, Outstanding Publication Award
Scientific/Oral Presentations, Abstracts
Science and Products
Filter Total Items: 418
Simultaneous modeling of habitat suitability, occupancy, and relative abundance: African elephants in Zimbabwe
The recent development of statistical models such as dynamic site occupancy models provides the opportunity to address fairly complex management and conservation problems with relatively simple models. However, surprisingly few empirical studies have simultaneously modeled habitat suitability and occupancy status of organisms over large landscapes for management purposes. Joint modeling...
Authors
Julien Martin, Simon Chamaillé-Jammes, James D. Nichols, Herve Fritz, James E. Hines, Christopher J. Fonnesbeck, Darryl I. MacKenzie, Larissa L. Bailey
Inferences about landbird abundance from count data: recent advances and future directions
We summarize results of a November 2006 workshop dealing with recent research on the estimation of landbird abundance from count data. Our conceptual framework includes a decomposition of the probability of detecting a bird potentially exposed to sampling efforts into four separate probabilities. Primary inference methods are described and include distance sampling, multiple observers...
Authors
James D. Nichols, L. E. N. Thomas, P.B. Conn
Estimating latent time of maturation and survival costs of reproduction in continuous time from capture-recapture data
In many species, age or time of maturation and survival costs of reproduction may vary substantially within and among populations. We present a capture-mark-recapture model to estimate the latent individual trait distribution of time of maturation (or other irreversible transitions) as well as survival differences associated with the two states (representing costs of reproduction)...
Authors
T. Ergon, Nigel G. Yoccoz, James D. Nichols
Filling a void: abundance estimation of North American populations of arctic geese using hunter recoveries
We consider use of recoveries of marked birds harvested by hunters, in conjunction with continental harvest estimates, for drawing inferences about continental abundance of a select number of goose species. We review assumptions of this method, a version of the Lincoln?Petersen approach, and consider its utility as a tool for making decisions about harvest management in comparison to...
Authors
Ray T. Alisaukas, K.L. Drake, James D. Nichols
An evaluation of density-dependent and density-independent influences on population growth rates in Weddell seals
Much of the existing literature that evaluates the roles of density-dependent and density-independent factors on population dynamics has been called into question in recent years because measurement errors were not properly dealt with in analyses. Using state-space models to account for measurement errors, we evaluated a set of competing models for a 22-year time series of mark-resight...
Authors
J.J. Rotella, William A. Link, James D. Nichols, G.L. Hadley, Robert A. Garrott, K.M. Proffitt
Habitat-specific breeder survival of Florida Scrub-Jays: Inferences from multistate models
Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection...
Authors
David R. Breininger, James D. Nichols, G.M. Carter, D.M. Oddy
Modeling species occurrence dynamics with multiple states and imperfect detection
Recent extensions of occupancy modeling have focused not only on the distribution of species over space, but also on additional state variables (e.g., reproducing or not, with or without disease organisms, relative abundance categories) that provide extra information about occupied sites. These biologist-driven extensions are characterized by ambiguity in both species presence and...
Authors
D.I. MacKenzie, James D. Nichols, M.E. Seamans, R. J. Gutierrez
Dynamic models for problems of species occurrence with multiple states
Recent extensions of occupancy modeling have focused not only on the distribution of species over space, but also on additional state variables (e.g., reproducing or not, with or without disease organisms, relative abundance categories) that provide extra information about occupied sites. These biologist-driven extensions are characterized by ambiguity in both species presence and...
Authors
Darryl I. MacKenzie, James D. Nichols, Mark E. Seamans, R. J. Gutierrez
Patterns and determinants of mammal species occurrence in India
Many Indian mammals face range contraction and extinction, but assessments of their population status are hindered by the lack of reliable distribution data and range maps. 2. We estimated the current geographical ranges of 20 species of large mammals by applying occupancy models to data from country-wide expert. We modelled species in relation to ecological and social covariates...
Authors
K.K. Karanth, James D. Nichols, James E. Hines, K. Ullas Karanth, N.L. Christensen
Modeling co-occurrence of northern spotted and barred owls: accounting for detection probability differences
Barred owls (Strix varia) have recently expanded their range and now encompass the entire range of the northern spotted owl (Strix occidentalis caurina). This expansion has led to two important issues of concern for management of northern spotted owls: (1) possible competitive interactions between the two species that could contribute to population declines of northern spotted owls, and...
Authors
Larissa L. Bailey, Janice A. Reid, Eric D. Forsman, James D. Nichols
Structured decision making as a conceptual framework to identify thresholds for conservation and management
Thresholds and their relevance to conservation have become a major topic of discussion in the ecological literature. Unfortunately, in many cases the lack of a clear conceptual framework for thinking about thresholds may have led to confusion in attempts to apply the concept of thresholds to conservation decisions. Here, we advocate a framework for thinking about thresholds in terms of a...
Authors
J. M. Martin, Michael Runge, James D. Nichols, Bruce L. Lubow, William L. Kendall
Dynamic multistate site occupancy models to evaluate hypotheses relevant to conservation of Golden Eagles in Denali National Park, Alaska
The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site...
Authors
Julien Martin, Carol L. McIntyre, James E. Hines, James D. Nichols, Joel A. Schmutz, Margaret C. MacCluskie
Science and Products
Filter Total Items: 418
Simultaneous modeling of habitat suitability, occupancy, and relative abundance: African elephants in Zimbabwe
The recent development of statistical models such as dynamic site occupancy models provides the opportunity to address fairly complex management and conservation problems with relatively simple models. However, surprisingly few empirical studies have simultaneously modeled habitat suitability and occupancy status of organisms over large landscapes for management purposes. Joint modeling...
Authors
Julien Martin, Simon Chamaillé-Jammes, James D. Nichols, Herve Fritz, James E. Hines, Christopher J. Fonnesbeck, Darryl I. MacKenzie, Larissa L. Bailey
Inferences about landbird abundance from count data: recent advances and future directions
We summarize results of a November 2006 workshop dealing with recent research on the estimation of landbird abundance from count data. Our conceptual framework includes a decomposition of the probability of detecting a bird potentially exposed to sampling efforts into four separate probabilities. Primary inference methods are described and include distance sampling, multiple observers...
Authors
James D. Nichols, L. E. N. Thomas, P.B. Conn
Estimating latent time of maturation and survival costs of reproduction in continuous time from capture-recapture data
In many species, age or time of maturation and survival costs of reproduction may vary substantially within and among populations. We present a capture-mark-recapture model to estimate the latent individual trait distribution of time of maturation (or other irreversible transitions) as well as survival differences associated with the two states (representing costs of reproduction)...
Authors
T. Ergon, Nigel G. Yoccoz, James D. Nichols
Filling a void: abundance estimation of North American populations of arctic geese using hunter recoveries
We consider use of recoveries of marked birds harvested by hunters, in conjunction with continental harvest estimates, for drawing inferences about continental abundance of a select number of goose species. We review assumptions of this method, a version of the Lincoln?Petersen approach, and consider its utility as a tool for making decisions about harvest management in comparison to...
Authors
Ray T. Alisaukas, K.L. Drake, James D. Nichols
An evaluation of density-dependent and density-independent influences on population growth rates in Weddell seals
Much of the existing literature that evaluates the roles of density-dependent and density-independent factors on population dynamics has been called into question in recent years because measurement errors were not properly dealt with in analyses. Using state-space models to account for measurement errors, we evaluated a set of competing models for a 22-year time series of mark-resight...
Authors
J.J. Rotella, William A. Link, James D. Nichols, G.L. Hadley, Robert A. Garrott, K.M. Proffitt
Habitat-specific breeder survival of Florida Scrub-Jays: Inferences from multistate models
Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection...
Authors
David R. Breininger, James D. Nichols, G.M. Carter, D.M. Oddy
Modeling species occurrence dynamics with multiple states and imperfect detection
Recent extensions of occupancy modeling have focused not only on the distribution of species over space, but also on additional state variables (e.g., reproducing or not, with or without disease organisms, relative abundance categories) that provide extra information about occupied sites. These biologist-driven extensions are characterized by ambiguity in both species presence and...
Authors
D.I. MacKenzie, James D. Nichols, M.E. Seamans, R. J. Gutierrez
Dynamic models for problems of species occurrence with multiple states
Recent extensions of occupancy modeling have focused not only on the distribution of species over space, but also on additional state variables (e.g., reproducing or not, with or without disease organisms, relative abundance categories) that provide extra information about occupied sites. These biologist-driven extensions are characterized by ambiguity in both species presence and...
Authors
Darryl I. MacKenzie, James D. Nichols, Mark E. Seamans, R. J. Gutierrez
Patterns and determinants of mammal species occurrence in India
Many Indian mammals face range contraction and extinction, but assessments of their population status are hindered by the lack of reliable distribution data and range maps. 2. We estimated the current geographical ranges of 20 species of large mammals by applying occupancy models to data from country-wide expert. We modelled species in relation to ecological and social covariates...
Authors
K.K. Karanth, James D. Nichols, James E. Hines, K. Ullas Karanth, N.L. Christensen
Modeling co-occurrence of northern spotted and barred owls: accounting for detection probability differences
Barred owls (Strix varia) have recently expanded their range and now encompass the entire range of the northern spotted owl (Strix occidentalis caurina). This expansion has led to two important issues of concern for management of northern spotted owls: (1) possible competitive interactions between the two species that could contribute to population declines of northern spotted owls, and...
Authors
Larissa L. Bailey, Janice A. Reid, Eric D. Forsman, James D. Nichols
Structured decision making as a conceptual framework to identify thresholds for conservation and management
Thresholds and their relevance to conservation have become a major topic of discussion in the ecological literature. Unfortunately, in many cases the lack of a clear conceptual framework for thinking about thresholds may have led to confusion in attempts to apply the concept of thresholds to conservation decisions. Here, we advocate a framework for thinking about thresholds in terms of a...
Authors
J. M. Martin, Michael Runge, James D. Nichols, Bruce L. Lubow, William L. Kendall
Dynamic multistate site occupancy models to evaluate hypotheses relevant to conservation of Golden Eagles in Denali National Park, Alaska
The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site...
Authors
Julien Martin, Carol L. McIntyre, James E. Hines, James D. Nichols, Joel A. Schmutz, Margaret C. MacCluskie