Date of Award

Winter 2023

Project Type


Program or Major

Natural Resources

Degree Name

Master of Science

First Advisor

Adrienne Kovach

Second Advisor

Heidi Holman

Third Advisor

Rebecca Rowe



Population Viability Analysis of a Remnant New England Cottontail Population in Southern New Hampshire

ByBrett Ferry University of New Hampshire, December 2023

Early successional forest in the northeastern United States provides habitat for a rich diversity of wildlife. Historically, weather events, beaver activity, and fires were continually creating a mosaic of early successional habitat. However, with modern land use very little early successional habitat is created, leading to the decline of the species’ that rely on it. New England cottontail (sylvilagus transitionalis) is an early successional obligate species whose population has been in decline since the mid-twentieth century. In response to its downward population trend a multistate range wide conservation initiative in the Northeastern U.S. is underway. My research focuses on evaluating a small remnant population of New England cottontail in Londonderry NH, using the population viability simulation Vortex. I collected population specific survival and dispersal data using radio collared rabbits for inclusion in the population viability analysis and supplemented other vital rates from the literature. I used a Kaplan-Meier survival analysis and survival ranged from 40-60% over four winter periods. Only 2% of collared rabbits dispersed from the habitat patch they were captured in. My population viability analysis consisted of two baseline simulations and nineteen altered scenarios. Altered scenarios simulated supplementation by captive release and increased survival, carrying capacity, and dispersal. There were no realistic scenarios that produced a viable population. However, the simulations highlighted how low dispersal connectivity and low recruitment were preventing the population from becoming viable in the Londonderry landscape.