Date of Award

Winter 2007

Project Type

Thesis

Program or Major

Natural Resources: Wildlife Ecology

Degree Name

Master of Science

First Advisor

John Litvaitis

Abstract

In areas that experience environmental seasonality, wildlife populations may undergo annual declines until the capacity of the environment is reached. The degree to which hunting may influence these populations depends on whether hunting mortality is additional to natural mortality (additive) or if natural mortality decreases as hunting increases (hunting is a compensatory mortality). To comply with the National Environmental Policy Act (NEPA) of 1969, Cape Cod National Seashore (CCNS) initiated an examination of the current rabbit hunting program in 2004. Because of the lack of current information of rabbit hunting within CCNS, the primary objective of this study was to determine whether hunting was an additive or compensatory form of mortality for cottontails. To address the hunting impact on eastern cottontails, I determined cause-specific mortality and survival rates of cottontails in hunted and non-hunted areas. Predation caused >70% of all deaths (N=71), whereas hunting caused 10% of all deaths (N=10) in all areas surveyed. There was substantially lower survival at hunted sites (0.05) than at non-hunted sites (0.19) during winter-spring of Year 1(1 December 2004 through 30 June 2005); there was no difference in survival between hunted (0.33) and non-hunted (0.40) sites during Year 2 (15 October 2005 through 30 June 2006). Lower survival in Year 1 was likely due to heavy and persistent snow that reduced food and cover resources. As a result, hunting was likely additive during that period. However, at least partial compensation seemed to have occurred during Year 2 when winter weather was less severe. The fact that CCNS is on a coastal peninsula limits the geographic range of the cottontails living there; this population may be more sensitive to stochastic weather than populations in the core of the range. Compared to predation, I do not believe that the current level and distribution of hunting influences cottontail populations at CCNS.

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