Date of Award

Winter 12-21-2018

Level of Access

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

Alessio Mortelliti

Second Committee Member

Erik J. Blomberg

Third Committee Member

Shawn Fraver

Abstract

Individual animals exhibit consistent behavioral tendencies over time and across contexts that have been termed personalities. Personality encapsulates an individual’s unique way of behaving and responding to life’s challenges, and since individuals vary in both personality type and their ability to exhibit behavioural plasticity, there are important links between an individual’s personality and its response to a changing environment; resulting in the study of animal personalities becoming increasingly popular in recent years. Previous research suggests that personality traits measured through standardized behavioural tests predict trappability (i.e. ‘trap happiness’ versus ‘trap shyness’). This relationship has been explored only within single species and never across environments, but it is essential to understand this link, because if personality drives trap response this suggests that samples obtained through active trapping methods are behaviorally-biased (perhaps weighing more heavily on the bold individuals) – violating any assumption of a random sample. Further, if personality traits predict trappability, it would be possible to extract personality data from long-standing mark-recapture datasets by using trappability as a proxy for personality. My thesis contributes to this growing field by clarifying the relationship between trappability and personality in Chapter 1, and by demonstrating a critical relationship between personality and an essential ecosystem process: seed dispersal in Chapter 2. To meet these goals, we designed a large-scale field experiment to measure personality and trappability in five small mammal species and across varying forest types. Using standardized tests, we quantified behaviour in deer mice (Peromyscus maniculatus), Southern red-backed voles (Myodes gapperi), American red squirrels (Tamiasciurus hudsonicus), woodland jumping mice (Napaeozapus insignis), and Northern short-tailed shrews (Blarina brevicauda). Using this same experimental design, we performed a detailed seed predation experiment to observe interactions with seeds by known-individuals across different forest treatments. Chapter 1 shows that, although we identified personality in all five of target species, personality traits did not predict different aspects of trappability, suggesting that our work examined a random-subset of the population (i.e. not behaviorally-biased) and that trappability cannot be used as a proxy for personality. In Chapter 2, we remotely observed interactions with seeds and assessed whether personality traits influenced key decisions in a natural environment and at vital stages of the dispersal process. Ultimately, this research provides the first evidence that personalities influence four critical stages of seed predation and dispersal by scatter-hoarding small mammal, and that conserving behavioral diversity could maintain a diversity of ecological functions by conserving individuals with certain personality traits.

Available for download on Monday, December 09, 2019

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