Michael A. Sawaya, Ph.D. (University of Tennessee, Sinopah Wildlife Research Associates)
Jeffrey B. Stetz, M.Sc. (University of Tennessee, Sinopah Wildlife Research Associates)
Frank T. van Manen, Ph.D. (United States Geological Survey)
Joseph D. Clark, Ph.D. (United States Geological Survey)
Population monitoring is essential for effective black bear (Ursus americanus) management, but uncertainty about applicability, strengths, and weaknesses of different techniques makes it difficult for wildlife managers to decide which methods and models are most appropriate to accomplish their objectives. The Northeast Black Bear Technical Committee was created by the Northeast Wildlife Administrators Association to facilitate transboundary research and management; the committee is comprised of black bear managers from the following 13 U.S. states and 6 Canadian provinces: Connecticut, Delaware, Massachusetts, Maryland, Maine, New Brunswick, Newfoundland, New Hampshire, New Jersey, New York, Nova Scotia, Ontario, Pennsylvania, Prince Edward Island, Quebec, Rhode Island, Vermont, Virginia, and West Virginia. Consequently, the Northeast Black Bear Technical Committee commissioned a technical report to investigate black bear population monitoring options for the Northeast.
1) to provide an overview of current status and management of American black bears in the Northeast United States and Canada.
2) to produce an in-depth review of reliable techniques to estimate population parameters and monitor population trends.
3) to provide guidance to agencies to better enable them to choose monitoring tools that best meet their management objectives and available resources.
We identified many suitable monitoring options for black bear managers in the Northeast, but there is no single best method for all bear populations and management objectives. One of the greatest dilemmas for bear managers today is that the most expensive monitoring methods (i.e., radiotelemetry, DNA-based mark-recapture) are also the methods that provide the most accurate and precise estimates of population parameters. However, less expensive methods (e.g., indices) are ultimately a poor investment when the data tell us little about bear populations and provide limited inference regarding the drivers of population change. To aid managers in selecting the appropriate monitoring methods and proper study design, we used simulations to evaluate a range of classes of models, including mark-resight, open, closed, and spatially-explicit mark-recapture, and demographic analyses. Acknowledging financial limitations, we urge managers to always strive to use the best population monitoring techniques available to address their objectives, particularly those methods that inform adaptive management and function across jurisdiction boundaries.
For more details, see our technical report to the Northeast Black Bear Technical Committee (pdf).
Northeast Black Bear Population Monitoring Report