Jeffrey Bromaghin, Ph.D.
My research broadly encompasses the development and application of statistical methods and models to improve our understanding of ecological processes that influence the survival, behavior, and reproduction of individual animals, and how individual-animal outcomes ultimately scale upward to shape the dynamics and demographics of entire populations and communities through time and space.
My research involves the development and application of new analytical methods and models to improve our understanding of wildlife population ecology, with a current emphasis on polar bears and other DOI trust species residing in Arctic and sub-Arctic ecosystems. Past work has included nest survival models, applications of genetics in wildlife models, size selectivity and the effects of selective exploitation, animal response to capture and handling, and mark-recapture methodology. Most current research involves the development of mark-recapture and integrated population models to improve our understanding of polar bear population dynamics in a warming Arctic and the use of biotracers (e.g. fatty acids, stable isotopes) to estimate predator diet composition and animal origins and movements. Research products provide valuable information to the public and management authorities from local to international levels, and many have broad applicability that advance the discipline of statistical ecology.
Professional Experience
2009 - Present Research Statistician, U.S. Geological Survey, Alaska Science Center
2000 - 2009 Statistician, U.S. Fish and Wildlife Service, Fisheries and Ecological Services, Alaska Region
1990 - 2000 Regional Biometrician, Alaska Dept. of Fish and Game, Commercial Fisheries Division
Education and Certifications
Ph.D. 1991 University of Wyoming Statistics
M.S. 1988 University of Wyoming Statistics
B.S. 1985 University of Alaska Wildlife Management
Affiliations and Memberships*
The International Biometric Society
The Wildlife Society
Ecological Society of America
Honors and Awards
2014 U. S. Geological Survey, Quality step increase for exceptional performance
2014 U. S. Geological Survey, STAR award for special achievement
2012 U. S. Geological Survey, STAR award for special achievement
2012 Stevan Phelps Award, American Fisheries Society (Bromaghin et al., 2011, TAFS 140:235-249)
2011 U. S. Geological Survey, STAR award for special achievement
2010 U. S. Geological Survey, STAR award for special achievement
2007 U. S. Fish and Wildlife Service, STAR award for exceptional performance
2007 U. S. Fish and Wildlife Service, Regional Director’s award for Science Excellence
2004 U. S. Fish and Wildlife Service, quality step increase for sustained exceptional performance
2001 U. S. Fish and Wildlife Service, STAR award for outstanding performance
1993 Letter of commendation, Alaska Dept. Fish and Game
1992 Deming Award for distinguished graduate program. Dept. of Statistics, University of Wyoming
Science and Products
Simultaneous estimation of diet composition and calibration coefficients with fatty acid signature data
Detect and exploit hidden structure in fatty acid signature data
Habitat degradation affects the summer activity of polar bears
Forecasting the relative influence of environmental and anthropogenic stressors on polar bears
Should fatty acid signature proportions sum to 1 for diet estimation?
Validation of mercury tip-switch and accelerometer activity sensors for identifying resting and active behavior in bears
Simulating realistic predator signatures in quantitative fatty acid signature analysis
Assessing the robustness of quantitative fatty acid signature analysis to assumption violations
Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis
Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline
Distance measures and optimization spaces in quantitative fatty acid signature analysis
Evaluating and ranking threats to the long-term persistence of polar bears
Science and Products
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Filter Total Items: 30
Simultaneous estimation of diet composition and calibration coefficients with fatty acid signature data
Knowledge of animal diets provides essential insights into their life history and ecology, although diet estimation is challenging and remains an active area of research. Quantitative fatty acid signature analysis (QFASA) has become a popular method of estimating diet composition, especially for marine species. A primary assumption of QFASA is that constants called calibration coefficients, whichAuthorsJeffrey F. Bromaghin, Suzanne M. Budge, Gregory W. Thiemann, Karyn D. RodeDetect and exploit hidden structure in fatty acid signature data
Estimates of predator diet composition are essential to our understanding of their ecology. Although several methods of estimating diet are practiced, methods based on biomarkers have become increasingly common. Quantitative fatty acid signature analysis (QFASA) is a popular method that continues to be refined and extended. Quantitative fatty acid signature analysis is based on differences in theAuthorsJeffrey F. Bromaghin, Suzanne M. Budge, Gregory W. ThiemannHabitat degradation affects the summer activity of polar bears
Understanding behavioral responses of species to environmental change is critical to forecasting population-level effects. Although climate change is significantly impacting species’ distributions, few studies have examined associated changes in behavior. Polar bear (Ursus maritimus) subpopulations have varied in their near-term responses to sea ice decline. We examined behavioral responses of twoAuthorsJasmine V. Ware, Karyn D. Rode, Jeffrey F. Bromaghin, David C. Douglas, Ryan H. Wilson, Eric V. Regehr, Steven C. Amstrup, George M. Durner, Anthony M. Pagano, Jay Olson, Charles T. Robbins, Heiko T JansenForecasting the relative influence of environmental and anthropogenic stressors on polar bears
Effective conservation planning requires understanding and ranking threats to wildlife populations. We developed a Bayesian network model to evaluate the relative influence of environmental and anthropogenic stressors, and their mitigation, on the persistence of polar bears (Ursus maritimus). Overall sea ice conditions, affected by rising global temperatures, were the most influential determinantAuthorsTodd C. Atwood, Bruce G. Marcot, David C. Douglas, Steven C. Amstrup, Karyn D. Rode, George M. Durner, Jeffrey F. BromaghinShould fatty acid signature proportions sum to 1 for diet estimation?
Knowledge of predator diets, including how diets might change through time or differ among predators, provides essential insights into their ecology. Diet estimation therefore remains an active area of research within quantitative ecology. Quantitative fatty acid signature analysis (QFASA) is an increasingly common method of diet estimation. QFASA is based on a data library of prey signatures, whiAuthorsJeffrey F. Bromaghin, Suzanne M. Budge, Gregory W. ThiemannValidation of mercury tip-switch and accelerometer activity sensors for identifying resting and active behavior in bears
Activity sensors are often included in wildlife transmitters and can provide information on the behavior and activity patterns of animals remotely. However, interpreting activity-sensor data relative to animal behavior can be difficult if animals cannot be continuously observed. In this study, we examined the performance of a mercury tip-switch and a tri-axial accelerometer housed in collars to deAuthorsJasmine Ware, Karyn D. Rode, Anthony M. Pagano, Jeffrey F. Bromaghin, Charles T. Robbins, Joy Erlenbach, Shannon Jensen, Amy Cutting, Nicole Nicassio-Hiskey, Amy Hash, Megan A. Owen, Heiko JansenSimulating realistic predator signatures in quantitative fatty acid signature analysis
Diet estimation is an important field within quantitative ecology, providing critical insights into many aspects of ecology and community dynamics. Quantitative fatty acid signature analysis (QFASA) is a prominent method of diet estimation, particularly for marine mammal and bird species. Investigators using QFASA commonly use computer simulation to evaluate statistical characteristics of diet estAuthorsJeffrey F. BromaghinAssessing the robustness of quantitative fatty acid signature analysis to assumption violations
Knowledge of animal diets can provide important insights into life history and ecology, relationships among species in a community and potential response to ecosystem change or perturbation. Quantitative fatty acid signature analysis (QFASA) is a method of estimating diets from data on the composition, or signature, of fatty acids stored in adipose tissue. Given data on signatures of potentialAuthorsJeffrey F. Bromaghin, Suzanne M. Budge, Gregory W. Thiemann, Karyn D. RodeDiet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis
Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using quantitative fatty acid signature analysis. Tissue analysis from 26 yAuthorsT B Haynes, Joel A. Schmutz, Jeffrey F. Bromaghin, S J Iverson, V. M. Padula, A E RosenbergerPolar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline
In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species asAuthorsJeffrey F. Bromaghin, Trent L. McDonald, Ian Stirling, Andrew E. Derocher, Evan S. Richardson, Eric V. Regehr, David C. Douglas, George M. Durner, Todd C. Atwood, Steven C. AmstrupDistance measures and optimization spaces in quantitative fatty acid signature analysis
Quantitative fatty acid signature analysis has become an important method of diet estimation in ecology, especially marine ecology. Controlled feeding trials to validate the method and estimate the calibration coefficients necessary to account for differential metabolism of individual fatty acids have been conducted with several species from diverse taxa. However, research into potential refinemenAuthorsJeffrey F. Bromaghin, Karyn D. Rode, Suzanne M. Budge, Gregory W. ThiemannEvaluating and ranking threats to the long-term persistence of polar bears
The polar bear (Ursus maritimus) was listed as a globally threatened species under the U.S. Endangered Species Act (ESA) in 2008, mostly due to the significant threat to their future population viability from rapidly declining Arctic sea ice. A core mandate of the ESA is the development of a recovery plan that identifies steps to maintain viable populations of a listed species. A substantive evaluAuthorsTodd C. Atwood, Bruce G. Marcot, David C. Douglas, Steven C. Amstrup, Karyn D. Rode, George M. Durner, Jeffrey F. Bromaghin - Software
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government