E. GWINNER! The phenomenon of bird migration with its large scale dimensions has attracted the attention of naturalists for centuries. Worldwide billions of birds leave their breeding grounds every autumn to migrate to areas with seasonally more favor able conditions. Many of these migrants travel only over a few hundred kilo meters but others cover distances equivalent to the circumference of the earth. Among these long-distance migrants are several billion birds that invade Africa every autumn from their West and Central Palaearctic breeding areas. In the Americas and in Asia the scope of bird migration is of a similar magnitude. Just as impressive as the numbers of birds are their achievements. They have to cope with the enormous energetic costs of long-distance flying. particularly while crossing oceans and deserts that do not allow replenishment of depleted fat reserves. They have to appropriately time the onset and end of migrations. both on a daily and annual basis. And finally. they have to orient their migratory movements in space to reach their species- or population-specific wintering and breeding grounds, irrespective of the variable climatic conditions along their migratory routes.

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.​

Animal Migration, Orientation, and Navigation presents the various aspects of animal migration, including the evolution of migration, climatic and meteorological influences, and bioenergetics. This book discusses the physiological control, sensory systems, orientation and navigation, and biological clocks and phenology aspects of animal migration. Organized into five chapters, this book begins with an overview of the migration strategies of animals in the context of a space continuum. This text then explains the influence of short- and long-term climatic cycles on the spectrum of migratory patterns in nature. Other chapters consider the energetic requirements of different migration strategies and the energy stores of the migrants. This book discusses as well the physiological basis of animal migration, with emphasis on endocrinal findings on the timing and energetic aspects of different migration strategies. The final chapter deals with the mechanisms used in direction finding by migrating animals. This book is a valuable resource for biologists and ecologists.

P. Berthold and E. Gwinnd Bird migration is an intriguing aspect of the living world - so much so that it has been investigated for as long, and as thoroughly, as almost any other natural phenomenon. Aristotle, who can count as the founder of scientific ornithology, paid very close attention to the migrations of the birds he ob served, but it was not until the reign of Friedrich II, in the first half of the 13th century, that reliable data began to be obtained. From then on, the data base grew rapidly. Systematic studies of bird migration were introduced when the Vogelwarte Rossitten was founded, as the first ornithological biological observation station in the world (see first chapter "In Memory of Vogelwarte Rossitten"). This area later received enormous impetus when ex perimental research on the subject was begun: the large-scale bird-ringing experiment initiated in Rossitten in 1903 by Johannes Thienemann (who was inspired by the pioneering studies of C. C. M. Mortensen), the experiments on photoperiodicity carried out by William Rowan in the 1920s in Canada and retention and release experiments performed by Thienemann in the 1930s in Rossitten, the first experimental study on the orientation of migratory birds. After the Second World War, migration research, while continuing in the previous areas, also expanded into new directions such as radar ornithology, ecophysiology and hormonal control mechanisms, studies of evolution, ge netics, telemetry and others.

This edition focuses on the employment situation of immigrants. For the first time, this report presents a “scoreboard” of labour-market integration of immigrants, as well as an analysis of wage differentials between immigrants and the native-born.

Provides a foundation for understanding the fascinating field of seismic processing. Written for the non-expert, this two-volume introductory text reveals the limitations and potential pitfalls of seismic data, prepares both seismic interpreters and acquisition specialists for working with seismic processing geophysicists, and much more.