Zugunruhe

Migratory restlessness is a technical term from the Ornithology and experimental behavioral biology. He referred to the increased motor activity of migratory birds in the days immediately before the beginning of their migratory routes, ie before the start of departure towards summer quarters ( in the spring) or winter quarters (in autumn). Particularly striking is the restlessness at night is that brutal ". During members of this large group of birds outside the migration period rest usually at night, they are active on migration periods at night, sometimes all night " Are migratory birds kept in so-called registration cages and so prevented from migration, can the Zugunruhe quantitatively, for example when moving perches are used, which are mounted on microswitches and their movements are recorded electronically.

The restlessness lasts as long on as the bird would pull in the wild: The study of more than 100 species showed " that the restlessness is a regular expression of the migratory behavior of wild conspecifics and provides information on the progress of the train in the wild. " After the return Zuggeschehens also caged birds back to their außerzuglichen day -night rhythm.

In Germany, for example, Wolfgang Wiltschko explored since the early 1970s, the magnetic sense of migratory birds and developed devices that were able to register the directions exactly, in which his test animals tried each preferred to fly. In addition, the frequency of movements could be registered except the direction in his apparatus. Furthermore, it could be shown that also completely isolated from the natural environment birds at exactly the time to be active motor to the pull of their own wild conspecifics.

Eberhard Gwinner and Peter Berthold also demonstrated on the example of the laboratory hand-reared birds, the seasonal migration due to internal - are initiated state changes and not in response to changes in the environment - hormonal.

837691
de