Meet Our Scientists

For a complete listing of our scientific and support staff at Patuxent, please use our Staff Directory, or search all USGS staff profiles.  

Below we’ve compiled a browsable list to help you learn about our scientists and their expertise; each name links to the scientist’s full profile and publications.

Alicia Berlin

Alicia Berlin began as an intern at USGS Patuxent Wildlife Research Center in 2001 and, ultimately, became a Research Wildlife Biologist in 2008. Her background is in physiological ecology (the science of linking the physiology of an animal with on the ground management actions) and ornithology. Her research interests include bioenergetics modeling of waterbirds, habitat utilization of Atlantic seabirds using state of the art tracking technologies and developing innovative techniques to determine underwater noise impacts on seabirds.

Adrianne Brand

Adrianne is a Wildlife Biologist focused on landscape-scale research to inform resource management decisions with amphibian populations, as part of the Amphibian Research and Monitoring Initiative. Current projects include investigating population change in the Shenandoah salamander, monitoring to inform management of amphibians in the National Capital Region of NPS, planning management options for vernal pools, and population status investigations for the WV spring salamander. 

Joel Carr

Joel is a research ecologist with a background in modelling.  Joel uses process based models to explore feedbacks mechanisms in natural systems and the potential emergence of nonlinear behaviors and alternate state dynamics.  Joel is currently examining impacts of changing climate drivers on coastal systems from sub-tidal seagrass meadows to upland forests.  In the past Joel has explored complex networks, human-environment interactions, and inequality within the population-water-food nexus.

Antonio Celis-Murillo

Antonio (Tony) is an Avian Biologist in the Bird Banding Laboratory (BBL), where he works with the BBL team to strengthen the data management system for bird banding and band encounters data sets, provide technical assistant to bird banders and coordinate efforts in North America and the Western Hemisphere. Antonio also works with specific banding data sets to examine bird population patterns, including bird migration, and studies various aspects of avian ecology and behavior with the overarching goal of improving conservation efforts

Terry Chesser

Terry is a Research Zoologist who uses molecular techniques to inform conservation and management of birds. Current research includes studies of the genomics of declining Hawaiian honeycreepers, gene flow and management units in birds of the Channel Islands, and genetics of migratory shorebirds. Also incorporates new knowledge of species limits and other taxonomic changes into formats (e.g., Checklist of North American Birds) usable by management agencies, describes new species and genera of birds, and uses phylogenetics to enhance our understanding of the generation and maintenance of avian diversity.

Sam Droege

Sam is a Wildlife Biologist who designs and develops survey and status programs for plants and animals from the refuge level to nationwide. His current emphasis is on native bee survey techniques, natural history, identification, and status data. He has created a continent set of identification guides for the 4000 species of bees, manuals, and published a wide range of papers on survey techniques and status of North American wildlife.

Serguei Drovetski

Serguei is a Biologist with a background in avian ecology, morphology, molecular phylogenetics, phylo- and biogeography, host-symbiont co-evolution, and avian microbiome.  His research is focused on avian microbiome and the effects of environmental stressors on wildlife and its microbiome at the molecular and biochemical levels.  His recent projects use novel “omics” approaches for understanding toxicological responses to environmental stressors (agrochemical pollution, Per- and polyfluoroalkyl substances) in wildlife and especially in its microbiome.

Mary Freeman

Mary is a Research Ecologist with a background in stream ecology and conservation of freshwater fishes.  Mary’s work includes field studies and analyses aimed at understanding how fishes and stream ecosystems respond to environmental change, to support natural resource management and conservation.  Recent projects include estimating effects of streamflow extremes on fish populations; analyzing population trends in imperiled stream fishes in the southeast U.S.; and quantifying effects of stream restoration on fishes.

Howard Ginsberg

Howie is a Research Ecologist that publishes widely on the ecology of vector-borne diseases, especially tick-transmitted infections such as Lyme disease, and on mosquito ecology. His emphasis is on understanding transmission dynamics and factors that influence human exposure to vector-borne zoonotic pathogens. This knowledge is used to develop efficient approaches to surveillance and management of vector-borne diseases that protect public health while minimizing negative effects on sensitive natural systems. Other interests include conservation of invertebrates and bee foraging ecology, especially the interactions between native and introduced species.

Evan Grant

Evan is a Research Wildlife Biologist with a background in forest and wetland ecology and herpetology.  He is the principle investigator of the US Geological Survey’s Amphibian Research and Monitoring Initiative (ARMI), northeast region. His research addresses questions related to wildlife population stressors such as environmental change and disease.  He uses decision theory and population modeling to inform wildlife management. Current Projects include dendritic network ecology, dynamics of vernal pool breeding amphibian populations, management of amphibian populations in the northeastern US, population modeling to support prelisting science, and identifying proactive management strategies to address emerging disease threats.

Glenn Guntenspergen

Glenn is a Research Ecologist with a background in landscape ecology and modeling. His research spans both freshwater and coastal wetland ecosystems and focuses on their response to changes in global change drivers and the implications for ecosystem conservation and restoration. His current research includes: the potential influence of sea level rise and other climatic drivers on coastal wetland persistence and ecosystem properties; the fate of Pacific Atoll mangroves to rising sea levels; and the effectiveness of management actions to combat sea-level rise and preserve endangered species habitat.

Paula Henry

Paula is a Research Physiologist with a background in behavioral endocrinology and wildlife toxicology. Her research interests include identifying physiologically and behaviorally relevant markers for evaluating sublethal effects of exposure to environmental contaminants and stressors on wildlife. Her work has brought together field, pen, and lab studies to address environmentally relevant responses of birds, amphibians, and reptiles. Current projects include evaluating real or perceived effects of extracting fossil fuel processes (e.g. UOG) and associated extreme habitat modifications on resident terrestrial wildlife; identifying avian response to emerging contaminants during embryonic development, sexual differentiation and reproduction; and applying baseline hematology and biochemical profiles as initial health indicators for diseased or stressed species of concern.

Jim Hines

Jim is a Computer Scientist who conducts statistical analyses, population modeling, and software development for capture-recapture, presence-absence, and other types of wildlife data.  Also, administration and content-development of WWW server (hardware and software).  Some of his most recent projects include the development of a graphical interface for digitizing features of box turtle shells, updating the presentation of BBS trend results with a user-friendly graphical interface, adding features/capabilities to a software package used for estimating patch occupancy parameters, and analyzing Northern Spotted Owl capture-recapture data.

Natalie Karouna-Renier

Natalie is a Research Ecologist with expertise in molecular toxicology. Her research focuses on understanding, detecting, and predicting the effects of environmental stressors on wildlife using genomic, transcriptomic, metabolomic, endocrine, and biochemical tools. Current research projects in her lab focus on immune system changes and susceptibility to disease in birds exposed to environmental contaminants; alterations in gut microbiomes and antibiotic resistance gene pools in birds exposed to urban and agricultural contaminants; hazard and toxicity of neonicotinoid pesticides to terrestrial species; and health status of wild birds exposed to contemporary contaminants (PFAS and novel flame retardants).

Abigail Lawson

Abby is a Postdoctoral Research Associate focused on wildlife population ecology and decision analysis. Her research background includes hierarchical modeling, demographic parameter estimation, movement ecology, and monitoring program optimization. She is currently developing an adaptive management framework to inform conservation decisions for eastern Black Rail populations on the Atlantic Coast.

William Link

Bill is a Mathematical Statistician with expertise in development of mathematical models and analytical tools for investigation of ecological questions and monitoring of wildlife populations.  His collaborations with quantitative ecologists and biologists have related to a wide range of taxa, and include long-term studies of Weddell seals and the development of canonical analyses of data from the North American Breed Survey and the Christmas Bird Count.  His current research includes application of Bayesian methods to hierarchical models, with emphasis on model selection and multimodel inference.

James Lyons

Jim is a Research Ecologist working in the areas of avian population ecology and dynamics and adaptive management.  His current work is focused on shorebird and marsh bird (i.e. Red Knots and Black Rails) for partners such as the FWS, Atlantic Coast Joint Venture and the NOAA Restore program.  Jim is well known for his work on Structured Decision Making to assist partners in tackling difficult naturel resource management issues.

Jennifer Malpass

Jenn is a biologist in the Bird Banding Lab (BBL). She helps manage over 80 million records of marked birds, leads novel collaborations with external organizations (non-governmental organizations, academia, agencies), and connects people to wildlife using nature’s greatest ambassadors. Jenn also serves at the BBL's liaison to the Flyway Technical Sections.

Jeff Marion

Jeff is a Recreation Ecologist with a focus on research and monitoring to evaluate environmental impacts resulting from recreational activity in protected natural areas.  Research to: 1) identify, measure, and manage recreation resource impacts, 2) model and understand the influence of use-related, environmental, and managerial factors, 3) evaluate the efficacy of educational, site management and, regulatory actions designed to avoid or minimize recreation impacts, and 4) support and improve carrying capacity planning and decision-making.

Dan McAuley

Dan is a Research Wildlife Biologist focused on conducting field research on migratory bird issues identified by the US Fish and Wildlife Service and other Department of Interior agencies.  Dan's current research includes a large scale woodcock productivity study in Maine and NY, a study of migratory woodcock in Cape May, NJ, and a banding study to determine survival and recruitment of common eiders using mark-recapture methods and band recovery analyses. He has also done an analysis of habitat along Woodcock Singing Ground survey routes in ME, VT, NH, MA, and NY, survival of American woodcock during fall migration using radio telemetry, and evaluating the effects of habitat management on American woodcock and neo-tropical birds. 

Hilary Neckles

Hilary is a Research Ecologist with a background in wetland and marine ecology. Her research focuses on explaining and predicting responses of estuarine and wetland ecosystems to human impacts, natural forces, and management interventions. Recent projects include developing appropriate indicators and approaches for monitoring and assessing seagrass, estuarine, and salt marsh ecosystems at local and regional scales; identifying the role of invasive European green crabs in eelgrass habitat destruction in the northwest Atlantic; and developing tools to help optimize salt marsh management decisions on northeastern national wildlife refuges.

Glenn Olsen

Glenn is the Veterinary Medical Officer with areas of study include sea ducks and cranes. Captive breeding of cranes, diseases of cranes and sea ducks. Satellite radio telemetry or just radio telemetry in general, release techniques for cranes. crane biology and ecology, sea duck ecology, veterinary medicine of sea ducks, cranes, waterfowl in general, raptors, and other avian species. 

Keith Pardieck

Keith is a Supervisory Wildlife Biologist who manages the USGS North American Breeding Bird Survey (BBS), an international avian monitoring program that provides annual population change data on more than 500 bird species. He has a background in Environmental Science with interests in avian research, monitoring and sampling techniques to further conservation and management efforts, and also has a keen interest in leveraging citizen participation in science to achieve goals. His recent and recurrent projects include development of the 2020 BBS Strategic Plan, ensuring ~150,000 BBS locations are sampled annually, ensuring the updated BBS data set released annually, improving the utility of USGS data for science by expanding the BBS portfolio to include annual location data, and exploring novel mark-recapture analyses to improve the utility of BBS data for addressing affects of climate change and other stressors on bird populations.

Suzanne Peurach

Suzy is new to the Bird Banding Lab but spent the last two decades as a Museum Specialist at the National Museum of Natural History. Her background is in mammalian systematics, ecology, and collections management with a special focus on hair microscopy, identifying mammalian components of aircraft strike remains, anthropological artifacts, food contaminants, and prey remains, including assistance to USGS invasive species programs. Suzy is also a seasoned field mammologist assisting with mammal surveys and specimen preparation in the Americas and Africa. She is an active member of the USGS Policy Working Group of the Collections Steering Committee, and assists the BBL with encounter reports, updating scientific nomenclature and answering requests from the public. Suzy also serves as an interface between PWRC and the USGS STEP-UP Program, spending one day per week in Reston.

Diann Prosser

Diann is a Research Wildlife Ecologist with a background in wetland ecology and ornithology.  Her research interests include using spatial modeling techniques to help answer questions related to wildlife stressors such as climate change and disease.  Some of her recent projects include using satellite telemetry and spatial modeling to investigate the role of wild birds in the spread of avian influenza viruses; using an integrated modeling approach to predict risk of disease transmission across the wild waterfowl – domestic poultry interface, and using mark-resight techniques to improve waterbird population estimates on a large restoration project in the Chesapeake Bay.

Barnett Rattner

Barnett is a Research Physiologist engaged in ecotoxicological investigations, risk assessments and scholarly evaluations of legacy and contemporary environmental pollutants (industrial contaminants, metals, pesticides, pharmaceuticals). His current research focus is on exposure and potential adverse effects of anticoagulant rodenticides, neonicotinoid insecticides and algal toxins on wildlife and other biota.  He represents the Department of the Interior on the statutory Interagency Coordinating Committee on the Validation of Alternative Methods and the Interagency Testing Committee of the Toxic Substances Control Act, and advises the Fish and Wildlife Service on the apparent safety of candidate nontoxic shot developed for use in hunting.

Matthew Rogosky

Matt has background in Avian Biology and Environmental Science and currently works as a Program Biologist for the USGS Bird Banding Laboratory.  His duties include management of the biotechnical components of the Bird Banding Lab's Banding and Encounter Database. He also is responsible for banding permit review related to auxiliary marking and manages the Bird Banding Lab's field activities including two long-term bird banding stations. 

Andy Royle

Andy is a Research Statistician engaged in the development of statistical methods and analytic tools for animal demographic modeling, statistical inference and sampling wildlife populations and communities. His current research is focused on hierarchical models of animal abundance and occurrence, Bayesian analysis, spatial modeling, machine learning and classification, and the development of spatially explicit capture-recapture models for the study of spatial structure and dynamics of animal populations.

Michael Runge

Mike is a Research ecologist with a research focuses on the use of decision theory and population modeling to inform wildlife management, with particular emphasis on the formal application of adaptive management.  Most of his research involves collaboration with Federal management agencies (U.S. Fish and Wildlife Service, Bureau of Reclamation, National Park Service, National Marine Fisheries Service, and others).  He has worked on projects with migratory birds, National Wildlife Refuges, endangered species, and marine mammals (including manatees and polar bears).  He co-designed the “Introduction to Structured Decision Making” and “Adaptive Management” courses for the National Conservation Training Center, and co-leads the joint USGS/FWS Structured Decision Making Workshops.

John Sauer

John is a USGS Senior Scientist with interests in population ecology and survey design and analysis. Current research and collaborations involve development of new approaches for summary, model selection, and display of data from the North American Breeding Bird Survey (BBS), collaborative analyses with a wide variety of partners from federal, state, and non-governmental conservation organizations, and a comprehensive review and redesign of the USFWS Waterfowl Breeding Population and Habitat Survey.

Daniel Twedt

Dan is a Research Wildlife Biologist focused on avian ecology within bottomland hardwood forests, including bird response to forest restoration and silvicultural management, and assessment of alternative restoration and management techniques. Ongoing projects address forest structure and bird response to silvicultural prescriptions targeting wildlife in bottomland hardwoods, survival and productivity of birds in bottomland forests, and landscape scale integration of national land cover and forest inventory databases for assessment of bird distribution and abundance.

Anna Tucker

Anna is a Postdoctoral Research Associate focused on wildlife population dynamics and predicting population responses to changing environmental conditions. Her research background includes population ecology, demographic estimation, hierarchical modeling, and applications to management and conservation. She is currently working on developing optimal adaptive management strategies under uncertain future change.

H. Brian Underwood

Brians is a Research Wildlife Biologist with a background in population demography, plant and community ecology and advanced numeracy. He has published widely on the biology and management of wild herbivores in protected natural areas and then across peri-urban landscapes. His current research focuses on climate-sensitivity of endotherms based on biophysical ecology including behavioral thermoregulation in moose and deer, patterns of river otter latrine visitation in a changeable environment, and pelage transition mismatches in snowshoe hare in the face of regional climate warming.

Nimish Vyas

Nimish is a research biologist driven by his interest in avian conservation.  His research focuses primarily on identifying and addressing threats to birds and their environments.  Research involves a variety of studies on birds, pollinators and mammalian invasive species but his interests also encompass a myriad of other anthropogenic hazards to birds (for example, energy development, light pollution, avian trafficking and poaching, and illegal killings).  Much of his research produces publications with real-world applicability and are used by natural resource managers, policy regulators, wildlife law enforcement agents, and U.S. Attorneys.

Neal Woodman

Neal is a Research Zoologist working in biodiversity, taxonomy, and systematics of mammals, with particular expertise with shrews and moles, treeshrews, bats, and rodents; short- and long-term biodiversity surveys; post-cranial anatomical adaptations and natural patterns of injury; use of archaeological faunas for interpreting past climatic change, with special interest in Egyptian animal mummies; early 19th century and medieval concepts of mammals; curation and care of systematic natural history collections.

David Ziolkowski, Jr.

Dave is a Wildlife Biologist in the North American Breeding Bird Survey (BBS) for which he fosters multi-level stakeholder and research partnerships, coordinates the growth and maintenance of the survey’s infrastructure, and collaborates in producing BBS-related research products.  His past research has spanned the fields of ecology, behavior, biogeography, evolutionary biology, and toxicology.  Dave is considered a technical expert on North American birds, but his interests and knowledge of the continent's other flora and fauna is extensive.