Doctor of Philosophy
Dr. M. Brock Fenton, Dr. Fred J. Longstaffe
Many aspects of North American bat migration are not well documented. Stable isotope analyses of animal tissues can elucidate migratory origin, but this technique has not been widely applied to bats. This dissertation i) uses fur stable isotope analyses to investigate North American bat migration and ii) highlights some of the strengths and weaknesses of this analytical technique when applied to bat systems. I conducted stable hydrogen, carbon, and nitrogen isotope analyses on fur from five bat species.
I documented δDfur heterogeneity in summer resident populations of Myotis lucifugus, Lasiurus borealis, Lasiurus cinereus, and Lasionycteris noctivagans. Stable hydrogen isotope composition varied systematically within and among individuals, age groups, species, sites, and over time. Bats from proximate colonies were discriminated using multi- isotope analyses and stable isotope correlations existed in some species.
I investigated the origins of fall migrant L. noctivagans and L. borealis in Ontario. Stable isotope evidence did not indicate that migrant L. noctivagans originated from a wide range of latitudes, or that latitudinal origin varied with time or migrant “wave”. Lasiurus borealis results were highly variable and further work is required before ecological conclusions can be drawn from stable isotope results from this species.
I investigated the annual migratory movements of tri-colored bats (Perimyotis subflavus), a presumed regional migrant. Stable hydrogen isotope results indicated that some bats engaged in southern migration, a behavior not previously described for this species. More males than females migrated south and southern migrants were at the latitudinal extremes of the species’ range.
Fraser, Erin E., "Stable isotope analyses of bat fur: Applications for investigating North American bat migration" (2011). Electronic Thesis and Dissertation Repository. 332.