Directed by Dr. Pete Marra, Laudato Si’ Professor of Biology and the Environment and director of the Earth Commons, the Marra Lab in Georgetown’s Department of Biology studies the ecology and conservation of birds throughout their whole lifecycles. Marra Lab research uses birds to help us define and understand broad environmental issues, tackling contemporary conservation challenges by addressing fundamental knowledge gaps at the intersection of ornithology, ecology and conservation biology.
Migratory connectivity is the geographic and temporal linking of individuals and populations between one life cycle stage and another, such as between breeding and wintering locations for a migratory bird. The Marra Lab has completed or is working on or contributing to many range-wide tracking studies.
Learn moreThe full annual cycle describes a bird’s ecology across the year. The Marra Lab evaluates the impacts of climate on migratory birds in the different stages of their annual cycle in order to assess future effects of climate change on species’ vulnerability and the biology of birds.
Urbanization has altered habitats, restructured avian communities, and influenced the range sizes and population dynamics of animal species. The Marra Lab researches how different anthropogenic changes to the natural world affect population trajectories of birds.
Learn MoreAs of October 2019, the Kirtland Warbler’s successful recovery has lead to its removal from the endangered species list. The Marra Lab conducted a 4-year adaptive management experiment to reduce the Warbler’s reliance on conservation efforts.
Learn MoreAlthough general threats to birds are well known (e.g., habitat loss, anthropogenic causes of mortality), we still cannot point to the specific limiting factors or causes of declines for most bird species. The Marra Lab investigates species- and population-specific limiting factors so conservation resources can be implemented in the highest-priority places
Learn MoreThe Migratory Connectivity Project is working on two volume book entitled “Discovering Unknown Migrations: The Atlas of Migratory Connectivity for the Birds of North America.” This book will fill knowledge gap about the migratory connectivity for the birds of North America
Learn MoreLaudato Si’ Professor of Biology and the Environment
Professor, McCourt School of Public Policy
Director, Georgetown University’s Earth Commons
Emeritus Senior Scientist, Smithsonian Migratory Bird Center
Pete comes to Georgetown University after a 20-year career at the Smithsonian Institution, most recently as Director of the Migratory Bird Center. He has a Ph.D. from Dartmouth College and has authored over 225 papers published in journals such as Science, Nature and Conservation Biology on various aspects of the biology and conservation of birds and other animals, as well as on topics as broad as urban disease ecology. He co-edited the frequently cited book – Birds of Two Worlds and recently published a second book – Cat Wars: The Devastating Consequences of Cuddly Killer. Pete lives in Takoma Park with his wife and two kids, is an avid fisherman, a gardener and cook.
Research Associate
Scientist Nathan Cooper detangles and endangered Kirtland’s Warbler from the mist net. Nathan Cooper at the Smithsonian Migratory Bird Center is doing research on federally endangered Kirtland’s warblers — tagging 100 of them with highly miniaturized nanotags in the Bahamas, and then using automated receiver towers that will monitor the entire breeding range in Michigan to relocate them. It is the first time anyone has been able to study the same individual birds on both the wintering and breeding grounds—their behavior, nesting success, physical condition, even changes in their internal and external micro-biome from one site to the other. This should be a gold mine of information on what biologists call carryover effects — the way conditions on the wintering grounds, which have long been ignored by migratory ecologists, impact the breeding success of birds thousands of miles to the north and many months (even years) later. Scientists are finding that winter conditions, not the quality of breeding habitat in the north, is the single biggest determinant for nesting success and the rapid rate of climate change in Central America and the Caribbean, especially persistent drought, makes this a critical issue for migratory bird conservation. More and more birds are facing poor conditions in the tropics, and paying a price in fewer eggs and chicks, and higher mortality.
Website: nathanwcooper.com
Google Scholar
PhD Student
Bryant is trained as a behavioral and population ecologist. His research interests primarily focus on the linkages between animal movement and population ecology with special interests dealing with populations of migratory land birds. His work on the ecology of migratory birds began with his work on differential migration in a population of Savanna Sparrows at Bowdoin College under Nat Wheelwright. Since then he has undertaken numerous field research positions working with the Black-throated Blue warblers at Hubbard Brook Experimental Forest, the stopover ecology of passerine migrants on the Gulf Coast with the University of Southern Mississippi, to the winter ecology of American redstarts in Jamaica with the Smithsonian Migratory Bird Center. His MSc focused on the stopover ecology of migratory warblers in the Great Lakes. By utilizing an automated radio telemetry array, he was able to determine the factors that influence migratory movement dynamics across western Lake Erie and Southern Ontario with implications on wind energy development throughout the Great Lakes. Bryant is currently pursuing his PhD at Cornell University’s Department of Natural Resources, and Cornell Lab of Ornithology, where he has returned to work in Jamaica on American Redstarts (advisors: Peter Marra & Amanda Rodewald) looking to develop upon his interests in the movement, behavioral, and population ecology of migratory birds.
Website: bryantdossman.weebly.com
Google Scholar
Research Associate
Brian is a quantitative ecologist and data scientist specializing in the ecology of birds in human-dominated landscapes. Brian earned a B.S. in Ecology from the University of North Carolina at Asheville in 2006 and a PhD in Quantitative Ecology from the University of North Carolina at Chapel Hill in 2015. Brian’s work utilizes mark-recapture, point count, radio and GPS tracking, citizen science, and GIS data to assess landscape and regional predictors of bird population dynamics, movement ecology, and community composition. As an expert-level computer programmer, he assists colleagues in quantifying field data and teaches professional workshops and graduate classes on Program R and data science. Currently, Brian is creating a data management system for storing and accessing field data and developing unique citizen science and education programs that engage the public in the ecology and conservation of urban systems.
Research Technician
Amy earned her B.S. in Ecology and Systematic Biology from California Polytechnic State University San Luis Obispo in 2003, and her M.S. in Natural Resources/Wildlife Biology, studying the spatial ecology of Common Ravens, from Humboldt State University in 2011. Amy is mapping the Bird Banding Laboratory’s database of band recoveries, which includes over 5 million recoveries spanning over one hundred years. This information, along with all of the tracking data for all avian species in North America, will be synthesized and compiled into the Atlas of Migratory Connectivity for North American birds. Amy is part of the Migratory Connectivity Project, which works to improve the understanding of migratory connectivity, to promote full annual and life cycle biology research, and to advance the technological tools needed to track birds.
Post-doctoral Researcher
Calandra is interested in the behavioral ecology and conservation of migratory birds. Her research aims to understanding how migratory birds interact with their environment throughout their annual cycle using both laboratory and field studies. For her postdoctoral research she is using satellite transmitters to track Yellow-billed cuckoos in order to study their movement ecology and identify spatiotemporal patterns of mortality. Stanley earned her bachelor’s and master’s of science in biology from York University, Canada, and her Ph.D. in biological sciences at the University of Maryland under the supervision of Dr. Peter Marra and Dr. Michele Dudash.
PhD Student
Henry graduated from Tufts University (Roll ‘Bos) in 2019 with a joint BS in Biology and Environmental Science. He grew up in Exeter, NH, where he discovered his passion for ornithology. He LOVES birds, and his desire to understand their ecology is what gets him out of bed in the morning (#ForTheBirds). Henry’s research interests lie at the intersection of conservation ornithology and tropical ecology, and his past research has focused on the breeding biology and dispersal of Gray Vireos (Vireo vicinior) in New Mexico, the use of remote audio recorders for surveying cryptic species in the Amazon, improving the conservation site network for migratory shorebirds in the Americas, and uncovering the life histories of Andean Cock-of-the-rocks (Rupicola peruvianus) and other understudied species in the cloud forests of Ecuador. At Georgetown, Henry plans to study the full annual cycle of Neotropical migratory wood-warblers, and use integrated population models to pinpoint factors driving their declines. With over 3.2 billion individual birds lost in North America since 1970, understanding and addressing the threats faced by these species is paramount for mitigating further declines.
PhD Student
Emily is an avian ecologist that has been working with birds for the last ten years. She comes to the Marra lab from working for the National Park Service in Alaska, where she studied the movements, ecology, and behavior of Denali’s resident and migratory birds. Prior to working at Denali National Park and Preserve, Emily completed her MSc at Kansas State University investigating the patterns and mechanisms to within-season breeding dispersal in grassland sparrows. Emily received her BSc in Wildlife Ecology and Conservation and BA degree in English literature from the University of Florida. Emily’s research interests center in migration ecology, with a particular interest in the evolutionary and ecological processes that give rise to variation in migratory behavior. Emily’s PhD research will focus on understanding the drivers that lead to different migratory strategies between palearctic and Nearctic migratory birds. Beyond her academic interests, Emily is passionate about outreach and the accessibility of science, and never foregoes an opportunity to get people excited about birds.
Website: emilyjwilliams.weebly.com
Twitter: @wayfaringwilly
Google Scholar
