John Sauer, Ph.D.


John Sauer is a Wildlife Biologist with the Patuxent Wildlife Research Center.  He has also worked as a Statistician with the U. S. Fish and Wildlife Service and as a Lecturer at the University of Kansas.  He is an Elective Fellow of the American Ornithologists' Union, and serves on the Board of Editors of Ecology, Ecological Monographs, and Avian Conservation and Ecology.  Education:  B. A. Rutgers College (Ecology); M. S. University of Wyoming (Zoology and Physiology); M. A. University of Kansas (Mathematics); M.Phil. and Ph.D. University of Kansas (Systematics and Ecology).

I participate in a wide variety of research projects, united by the general themes of population ecology, survey design and analysis, geographic and temporal analysis of population change, analysis of count data, geographical ecology, and summary and display of large-scale surveys.  My current projects include:

Analysis of population change from count data-I am involved in a series of research projects associated with analysis of population change from count data.  Along with a variety of collaborators, I develop methods for analysis of counts in which counts are modeled hierarchically, as over-dispersed Poisson random variables, allowing for adjustment of both factors that influence visibility of animals and factors that actually influence population sizes.  These methods are presently being implemented for the North American Breeding Bird Survey, the Christmas Bird Count, the Mourning Dove Call-Count Survey, breeding waterfowl surveys in the Northeastern United States and Canada, and the Woodcock Singing-ground Survey.  The methods are also used for spatial modeling and landscape level analyses, addressing questions relevant to conservation and ecology.  I conduct yearly analyses of all North American Breeding Bird Survey data, and consult with researchers and managers who use the database. 

Development of internet-based procedures for summary and analysis of survey data-In collaboration with other Patuxent staff, I have developed a series of web sites that allow users access to information from the North American Breeding Bird Survey and other datasets.  Survey data can be accessed at several geographic scales, from individual sample units to continental summaries.  Custom analyses of population change can be conducted for regions, species, and time periods specified by users.  Website address:

Development of national monitoring program for the bald eagle- I was a co-investigator on a project to initiate pilot surveys for bald eagles in Maine, Minnesota, Florida, and Washington, and to develop a draft monitoring program for the species.  This work is presently being used to develop and implement the monitoring program nationwide.

Estimation of community attributes from survey data- I have participated in a series of projects involved with developing procedures for estimation of species richness from count data such as the those collected in the North American Breeding Bird Survey.  I organized a field project to collect bird survey data on the Patuxent Research Refuge to develop community-level models of bird populations and predict the consequences of alternative management options on a collection of species of management interest.

Association of remote-sensed habitat data with survey data- I have participated in several projects that associate remote-sensed habitat data with animal survey data.  A current project  analyzes the influence of roads on Breeding Bird Survey results using remotely-sensed landuse data.  The project involves random sampling of possible route paths on and off roads to provide a probabilistic assessment of the effects of roadside sampling.  Because remotely-sensed landuse change information is now available, the project also provides an assessment of the relative rates of change of habitats on and off roads.