Biogeography: Stable Isotope Applications
The distribution of species across the landscape is of great interest to conservation biology. Habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences. However, for species with cryptic or migratory life histories, we often lack sufficient detail about habitat usage and in many cases, general location and activity information are unavailable. Extrinsic markers, such as tags and bands, have proven to be rather ineffective due to low returns. Intrinsic markers, such as stable isotopes, on the other hand have great potential because inference is not constrained by recapture. Rather, important insights regarding movement and habitat use can be derived from both metabolically active and inactive tissues of many wildlife species. This approach is cost-effective and has led to important findings regarding the location of wintering and breeding grounds, stop over sites, and the concept of migratory connectivity.