University of Western Ontario - Electronic Thesis and Dissertation Repository

Degree

Master of Science

Program

Biology

Supervisor

Dr. Chris Guglielmo

Abstract

Although fat deposition during stopover in migrating passerine birds has been extensively studied, changes in lean mass during refuelling are not well understood. I used quantitative magnetic resonance (QMR) analysis to measure the deposition of fat and lean mass for both recaptured and single capture migrant passerines in spring and fall at Long Point, Ontario. Both the recapture analysis and single capture regression analysis indicated a substantial contribution of lean mass to overall increases in total body mass. Some of the variation in the relative deposition of fat and lean mass was explained by sex, age and season. I then used radio-telemetry and mark-recapture analysis to investigate whether QMR affects a bird’s magnetic compass or stopover duration. QMR had no effect on stopover duration and departure orientation of migrating Black-throated Blue Warblers. QMR slightly increased stopover duration in adult White-throated Sparrows in fall, but not in spring. My study demonstrates that lean mass deposition is substantial and dynamic, and that QMR is a safe and effective technology to study fuel deposition of migrant birds in the field.