Passerine Migration

Most birds cannot cover the distance between their breeding and winter quarters in one hop. They have to make multiple flights alternated with stopovers. Which factors govern the birds’ decisions to stop, to stop for how long, when to resume flight? What is better – to accumulate much fuel and to make long flights for many hundreds of kilometres, or to travel in small steps? Is it necessary to find habitats similar to the breeding ones or other habitats would do? Are long migratory flights indeed so costly energetically as usually assumed? This monograph summarizes our current knowledge on the ecology of songbird migrants during migratory stopovers and on their behaviour.​

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.