Publication Date



Open access

Embargo Period


Degree Name

Master of Science (MS)


Marine Affairs and Policy (Marine)

Date of Defense


First Committee Member

Marialuisa E. Estevanez

Second Committee Member

Daniel O. Suman

Third Committee Member

Jill L. Richardson


Studying the population parameters of marine mammals requires that individuals be identified both spatially and temporally. Traditionally, to identify individuals in the field, animals have been captured and physically marked with a unique feature, allowing the individual to be identified in the future. This method known as Capture-Mark-Recapture (CMR) has been widely utilized to analyze marine mammal populations. While quite effective, traditional CMR is invasive and poses potential risk for both animals and researches. More recently, with advanced technology and camera equipment a far less invasive and more cost effective method of Photo-identification based Mark Recapture has been developed (PMR). To assess the efficacy of computer aided matching software and the applicability of such software for future pinniped studies, a photographic based mark recapture study was conducted across the 2011-2014 harbor seal seasons using both manual and computer aided methods to determine if the Long Island, NY population display site fidelity, in that they return to the same haul-out location over multiple seasons. Additionally, manual and computer methods were compared for accuracy and their potential use in future pinniped studies.


photo-identification; marine mammals; pinniped; site fidelity