Assistant Unit Leader - Colorado Cooperative Fish and Wildlife Research Unit
Research Interests
My interests are in the development, application, and evaluation of methods in quantitative ecology. Current research focuses on several areas of capture-recapture statistical methodology, the conceptual development of adaptive resource management and its application to decision problems, and population dynamics of sandhill cranes, albatross, sea turtles, and manatees.
Teaching Interests
I teach courses in population analysis and demographic estimation, and wildlife management science.
Professional Experience
Assistant Unit Leader, Colorado Cooperative Fish and Wildlife Research Unit, 2010-
Education and Certifications
Ph D North Carolina State University 1992
MS North Carolina State University 1990
MS North Carolina State University 1985
BBA University of Cincinnati 1982
Science and Products
Filter Total Items: 75
Range-wide sources of variation in reproductive rates of northern spotted owls
We conducted a range-wide investigation of the dynamics of site level reproductive rate of northern spotted owls using survey data from 11 study areas across the sub-species geographic range collected during 1993–2018. Our analytical approach accounted for imperfect detection of owl pairs and misclassification of successful reproduction (i.e., at least one young fledged) and contributed further in
Incorporating antenna detections into abundance estimates of fish
Autonomous passive integrated transponder (PIT) tag antennas are commonly used to detect fish marked with PIT tags but cannot detect unmarked fish, creating challenges for abundance estimation. Here we describe an approach to estimate abundance from paired physical capture and antenna detection data in closed and open mark-recapture models. Additionally, for open models, we develop an approach tha
Range-wide declines of northern spotted owl populations in the Pacific Northwest: A meta-analysis
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at the center of forest management issues in this region. The immediate threats to this federally listed species include habitat loss and competition with barred owls (Strix varia), which invaded from eastern North America. We conducted a prospective meta-analysis to assess
Opinion: A preferred approach for dealing with reproducibility and replicability in science
Science impacts our daily lives and guides national and international policies (1). Thus, results of scientific studies are of paramount importance; yet, there are concerns that many studies are not reproducible or replicable (2). To address these concerns, the National Research Council conducted a Consensus Study [NASEM 2019 (3)] that provides definitions of key concepts, discussions of problems,
Partial migration and spawning movements of humpback chub in the Little Colorado River are better understood using data from autonomous PIT tag antennas
Choosing whether or not to migrate is an important life history decision for many fishes. Here we combine data from physical captures and detections on autonomous passive integrated transponder (PIT) tag antennas to study migration in an endangered fish, the humpback chub (Gila cypha). We develop hidden Markov mark-recapture models with and without antenna detections and find that the model fit wi
Factors influencing Cinnamon Teal nest attendance patterns
Patterns of nest attendance in birds result from complex behaviours and influence the success of reproductive events. Incubation behaviours vary based on individual body condition, energy requirements and environmental factors. We assessed nest attendance patterns in Cinnamon Teal Spatula cyanoptera breeding in the San Luis Valley of Colorado in 2016–2017 using trail and video cameras to observe b
Optimal spatial prioritization of control resources for elimination of invasive species under demographic uncertainty
Populations of invasive species often spread heterogeneously across a landscape, consisting of local populations that cluster in space but are connected by dispersal. A fundamental dilemma for invasive species control is how to optimally allocate limited fiscal resources across local populations. Theoretical work based on perfect knowledge of demographic connectivity suggests that targeting local
Nest site selection influences cinnamon teal nest survival in Colorado
Nest survival of ducks is partially a function of the spatiotemporal characteristics of the site at which a bird chooses to nest. Nest survival is also a fundamental component of population growth in waterfowl but is relatively unstudied for cinnamon teal (Spatula cyanoptera). We investigated cinnamon teal nest survival in a managed wetland complex in southern Colorado, USA, and assessed nest site
A stage-based model of manatee population dynamics
A stage-structured population model for the Florida manatee (Trichechus manatus latirostris) was developed that explicitly incorporates uncertainty in parameter estimates. The growth rates calculated with this model reflect the status of the regional populations over the most recent 10-yr period. The Northwest and Upper St. Johns River regions have growth rates (λ) of 1.037 (95% interval, 1.016–1.
Capture-recapture analysis for estimating manatee reproductive rates
Modeling the life history of the endangered Florida manatee (Trichechus manatus latirostris) is an important step toward understanding its population dynamics and predicting its response to management actions. We developed a multi-state markresighting model for data collected under Pollock's robust design. This model estimates breeding probability conditional on a female's breeding state in the pr
Selecting ecological models using multi-objective optimization
Choices in ecological research and natural resource management require balancing multiple, often competing objectives. Examples include maximizing species persistence in a wildlife conservation context, while minimizing cost, or balancing opposing stakeholder objectives when managing wildlife populations. Multiple-objective optimization (MOO) provides a unifying framework for solving multiple obje
Characterizing residence patterns of North Atlantic right whales in the southeastern U.S. with a multistate open robust design model
Effective conservation of endangered North Atlantic right whales (Eubalaena glacialis) requires information about their spatio-temporal distribution. Understanding temporal distribution is particularly important, because a portion of the population migrates between high latitude summer feeding grounds off the northeastern U.S. and Canadian Maritimes coasts and lower latitude calving and wintering
Non-USGS Publications**
Ruiz-Gutierrez, V., W. L. Kendall, J. F. Saracco, and G. C. White. Modeling dynamics for resident and transient individuals: a case study using uncertain state models for migratory birds. Journal of Applied Ecology, DOI: 10.1111/1365-2664.12655
Garcia-Cruz, M. A., M. Lampo, C. L. Penaloza, W. L. Kendall, G. Sole, and K. M. Rodriguez-Clark. 2015.Population trends and survival of nesting green sea turtles (Chelonia mydas) on Aves Island, Venezuela. Endangered Species Research 29:101-116.
Lyons, J. E., W. L. Kendall, J. A. Royle, S. J. Converse, B. A. Andres, and J. B. Buchanan. 2015. Population size and stopover duration estimation using mark-resight data and Bayesian analysis of a superpopulation model. Biometrics DOI: 10.1111/biom.12393.
Pearson, K. N., W. L. Kendall, D. L. Winkelman, and W. R. Persons. 2015. Evidence for skipped spawning in the endangered humpback chub (Gila cypha) with implications for demographic parameter estimates. Canadian Journal of Fisheries and Aquatic Sciences 170:50-59
Chambert, T., Kendall, W. L., Hines, J. E., Nichols, J. D., Pedrini, P., Waddle, J. H., Tavecchia, G., Walls, S. C. and Tenan, S. (2015), Testing hypotheses on distribution shifts and changes in phenology of imperfectly detectable species. Methods Ecol Evol, 6: 638–647. doi:10.1111/2041-210X.12362
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Publications
Filter Total Items: 75
Range-wide sources of variation in reproductive rates of northern spotted owls
We conducted a range-wide investigation of the dynamics of site level reproductive rate of northern spotted owls using survey data from 11 study areas across the sub-species geographic range collected during 1993–2018. Our analytical approach accounted for imperfect detection of owl pairs and misclassification of successful reproduction (i.e., at least one young fledged) and contributed further inIncorporating antenna detections into abundance estimates of fish
Autonomous passive integrated transponder (PIT) tag antennas are commonly used to detect fish marked with PIT tags but cannot detect unmarked fish, creating challenges for abundance estimation. Here we describe an approach to estimate abundance from paired physical capture and antenna detection data in closed and open mark-recapture models. Additionally, for open models, we develop an approach thaRange-wide declines of northern spotted owl populations in the Pacific Northwest: A meta-analysis
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at the center of forest management issues in this region. The immediate threats to this federally listed species include habitat loss and competition with barred owls (Strix varia), which invaded from eastern North America. We conducted a prospective meta-analysis to assessOpinion: A preferred approach for dealing with reproducibility and replicability in science
Science impacts our daily lives and guides national and international policies (1). Thus, results of scientific studies are of paramount importance; yet, there are concerns that many studies are not reproducible or replicable (2). To address these concerns, the National Research Council conducted a Consensus Study [NASEM 2019 (3)] that provides definitions of key concepts, discussions of problems,Partial migration and spawning movements of humpback chub in the Little Colorado River are better understood using data from autonomous PIT tag antennas
Choosing whether or not to migrate is an important life history decision for many fishes. Here we combine data from physical captures and detections on autonomous passive integrated transponder (PIT) tag antennas to study migration in an endangered fish, the humpback chub (Gila cypha). We develop hidden Markov mark-recapture models with and without antenna detections and find that the model fit wiFactors influencing Cinnamon Teal nest attendance patterns
Patterns of nest attendance in birds result from complex behaviours and influence the success of reproductive events. Incubation behaviours vary based on individual body condition, energy requirements and environmental factors. We assessed nest attendance patterns in Cinnamon Teal Spatula cyanoptera breeding in the San Luis Valley of Colorado in 2016–2017 using trail and video cameras to observe bOptimal spatial prioritization of control resources for elimination of invasive species under demographic uncertainty
Populations of invasive species often spread heterogeneously across a landscape, consisting of local populations that cluster in space but are connected by dispersal. A fundamental dilemma for invasive species control is how to optimally allocate limited fiscal resources across local populations. Theoretical work based on perfect knowledge of demographic connectivity suggests that targeting localNest site selection influences cinnamon teal nest survival in Colorado
Nest survival of ducks is partially a function of the spatiotemporal characteristics of the site at which a bird chooses to nest. Nest survival is also a fundamental component of population growth in waterfowl but is relatively unstudied for cinnamon teal (Spatula cyanoptera). We investigated cinnamon teal nest survival in a managed wetland complex in southern Colorado, USA, and assessed nest siteA stage-based model of manatee population dynamics
A stage-structured population model for the Florida manatee (Trichechus manatus latirostris) was developed that explicitly incorporates uncertainty in parameter estimates. The growth rates calculated with this model reflect the status of the regional populations over the most recent 10-yr period. The Northwest and Upper St. Johns River regions have growth rates (λ) of 1.037 (95% interval, 1.016–1.Capture-recapture analysis for estimating manatee reproductive rates
Modeling the life history of the endangered Florida manatee (Trichechus manatus latirostris) is an important step toward understanding its population dynamics and predicting its response to management actions. We developed a multi-state markresighting model for data collected under Pollock's robust design. This model estimates breeding probability conditional on a female's breeding state in the prSelecting ecological models using multi-objective optimization
Choices in ecological research and natural resource management require balancing multiple, often competing objectives. Examples include maximizing species persistence in a wildlife conservation context, while minimizing cost, or balancing opposing stakeholder objectives when managing wildlife populations. Multiple-objective optimization (MOO) provides a unifying framework for solving multiple objeCharacterizing residence patterns of North Atlantic right whales in the southeastern U.S. with a multistate open robust design model
Effective conservation of endangered North Atlantic right whales (Eubalaena glacialis) requires information about their spatio-temporal distribution. Understanding temporal distribution is particularly important, because a portion of the population migrates between high latitude summer feeding grounds off the northeastern U.S. and Canadian Maritimes coasts and lower latitude calving and winteringNon-USGS Publications**
Ruiz-Gutierrez, V., W. L. Kendall, J. F. Saracco, and G. C. White. Modeling dynamics for resident and transient individuals: a case study using uncertain state models for migratory birds. Journal of Applied Ecology, DOI: 10.1111/1365-2664.12655Garcia-Cruz, M. A., M. Lampo, C. L. Penaloza, W. L. Kendall, G. Sole, and K. M. Rodriguez-Clark. 2015.Population trends and survival of nesting green sea turtles (Chelonia mydas) on Aves Island, Venezuela. Endangered Species Research 29:101-116.Lyons, J. E., W. L. Kendall, J. A. Royle, S. J. Converse, B. A. Andres, and J. B. Buchanan. 2015. Population size and stopover duration estimation using mark-resight data and Bayesian analysis of a superpopulation model. Biometrics DOI: 10.1111/biom.12393.Pearson, K. N., W. L. Kendall, D. L. Winkelman, and W. R. Persons. 2015. Evidence for skipped spawning in the endangered humpback chub (Gila cypha) with implications for demographic parameter estimates. Canadian Journal of Fisheries and Aquatic Sciences 170:50-59Chambert, T., Kendall, W. L., Hines, J. E., Nichols, J. D., Pedrini, P., Waddle, J. H., Tavecchia, G., Walls, S. C. and Tenan, S. (2015), Testing hypotheses on distribution shifts and changes in phenology of imperfectly detectable species. Methods Ecol Evol, 6: 638–647. doi:10.1111/2041-210X.12362**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.