Cooperative Fish and Wildlife Research Units Program: Pennsylvania
Education, Research and Technical Assistance for Managing Our Natural Resources

Pennsylvania Project

Surveillance and monitoring of river otter in Pennsylvania

August 2012 - December 2014


Participating Agencies

  • Pennsylvania Game Commission

An effective surveillance strategy and estimate of population size is necessary to better understand river otter distribution and abundance in northeastern Pennsylvania and to develop methods to estimate and monitor river otter populations statewide. Non-invasive genetic sampling is feasible and efficient method to estimate population size of elusive species such as river otter. Although the condition of fecal DNA is of great importance, collection methods and season (i.e., fresh samples collected in winter) can improve quality of DNA used in population identification. Using the proper number of microsatellite loci (i.e., 8–10) can also enable identification of individual otter use of each latrine. Identification of individual otters will enable a genetic mark-recapture estimate of population size from scat sampling provided a thorough survey of latrines in a define area is conducted.

Presentations Presentation Date
Forman, N.S., T. Hardisky, M. Lovallo, W.D. Walter. 2014. Monitoring river otter populations in northeastern Pennsylvania using non-invasive genetic sampling and spatial capture-recapture models. The 21st Annual Wildlife Society Conference, Pittsburgh, PA.

October 2014
Forman, N.F., and W.D. Walter. 2013. Population estimates of river otters in northeastern Pennsylvania using non-invasive genetic sampling. The Wildlife Society Annual Conference, Milwaukee, WI October 2013
Theses and Dissertations Publication Date
Forman, N.S. 2015. River otter population monitoring in Northeastern Pennsylvania using non-invasive genetic sampling and spatial capture-recapture models. The Pennsylvania State University, University Park, PA, 77 pp. December 2015