Document Type

Dissertation

Degree

Doctor of Philosophy

Major

Biology, Ecology

Date of Defense

7-21-2008

Graduate Advisor

Bette A. Loiselle, PhD

Committee

Blake, John

Parker, Patricia

Bradbury, Jack

Abstract

In lekking species, males aggregate at display grounds (?leks?) that females visit to copulate. Lekking systems are non-resource-based and males vary widely in reproductive output. This dissertation investigates how spatial and temporal factors influence lekking dynamics and female mate choice in the blue-crowned manakin Lepidothrix coronata. The first chapter deals with spatial dynamics of lekking behavior, and investigates whether leks are formed by the establishment of males on sites of high female density (?hotspot hypothesis?). Predictive maps of female spatial distribution were built based on field data and contrasted to the lek distribution. Leks were located in sites where males would encounter less females than expected by chance, partially as a result from differences in sex-specific habitat preferences. The second chapter is related to temporal aspects of lekking behavior, and investigates how leks are formed and change over time, and how leks, which are very traditional in location, can persist in face of relatively high male turnover. The fate of individual territorial males was followed for 4 years at up to 15 leks to estimate rates of male persistence at territories, recruitment, and expected tenure times. These estimates were used to simulate changes in lek size and composition over time. Results suggest that rates of male recruitment and disappearance compensate each other such that leks may persist for several decades after the original males have disappeared from them. In the third chapter, molecular analyses of paternity and behavioral observations were used to investigate the process of female mate choice at two spatial scales, within- and among-leks. Females moved beyond their regular home ranges to mate, suggesting that they increase travel costs to assess more potential mates. Although there was not a general preference for larger leks, females nesting close to small leks travelled further and mated at larger leks. Siring males were not less related to females or more heterozygous than expected by chance. Within leks, siring male were those with higher vocalization rates. Because vocalization rates changed according to lek sizes, however, they should not be a reliable indicator of male quality in most leks.

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Biology Commons

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