This monograph summarizes the results of studying passerine migration, mainly that of long-distance nocturnal migrants. Migratory stopovers and migratory flights are shown to be closely interconnected. The main quantitative parameters of stopovers, i.e., their duration, fuel deposition rate and overall energy efficiency, govern the potntial range of migratory flights. The quantitative energetic parameters of stopovers should not be studied separately from the stopover behaviour of birds, especially from their habitat selection and use and their spatial behaviour. The energy costs of migratory flight in species adapted for migration are significantly lower than hitherto assumed. A critique of optimal migration theory is presented and a qualitative model of stopover behaviour of migrating passerines is put forward.
The monograph represents a valuable resource for ornithologists, zoologists, ecologists, conservationists, and students of biology.