Meeting Abstract
Island rodents are often larger, less aggressive and tend to live at higher and more stable population densities than their mainland counterparts. To test whether island life also affects the stress physiology of rodents, we collected hair and fecal samples from white-footed mice (Peromyscus leucopus) over two summers from islands (n = 6) and mainland locations (n=5) in the Thousand Islands region of the St. Lawrence River. This archipelago has been previously featured in studies of biogeographic theory. Hair provides an integrated biomarker of long-term (weeks-months) glucocorticoid levels, while feces provide a shorter-term (hours-days) measure of hormone metabolites, allowing for different time periods of stress to be compared. To determine if insular mouse populations in the Thousand Islands demonstrate traits typical of “island syndrome,” we also used mark-recapture to measure population density, recorded morphological measurements and performed behavioural assays. Results will be discussed in relation to island size and degree of isolation from the mainland and population demographics.
