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Large-scale monitoring of animal movements aloft

Investigating the spatio-temporal patterns of aerial animal movements using radar

Did you know that myriads of birds, bats, and insects are flying to migrate, disperse, forage, or reproduce, day and night? For instance, two thirds of migratory birds fly at night! Radar can reveal what mostly remains visually unseen. We monitor the movements of flying animals and relate them to environmental factors, in order to predict their distributions and assess their vulnerability to anthropogenic infrastructures (e.g. wind energy) and activities (e.g. aviation).

Domain Research
Unit Bird Migration
Topic Birds and Human Beings, Ecology, Migratory Birds
Habitat alpine habitats, farmland, forest, meadows and pastures, rivers & streams, rocky terrain, semi-open farmland, settlements, wasteland, wetlands
Project start 1993
Project status ongoing
Project management Baptiste Schmid
Project region Africa, America, Asia, Europe


Project objectives

Our radar studies aim at:

  • Continuous and automatic monitoring of migration by radar
  • Investigating environmental influences on the temporal and spatial distributions of migratory flows, primarily birds
  • Examining the environmental influence on individual flight behaviour
  • Forecasting the temporal and spatial distributions of migratory birds, aloft and on the ground


We use a combination of small-scale radar and large-scale weather radar to map the spatio-temporal distribution of migratory flows. Read more on radar technology here. To complement the lack of information on species identity of radar data, we work on workflows to integrate radar data with other source of information, such as nocturnal flight calls and ground observations from citizen.


Monitoring migratory flows with radar allows us to investigate the environmental impacts from local to continental scales. It provides insights on how birds achieve their remarkable performance during migration. It also supports conservation actions by giving cues on how to mitigate effects of anthropogenic environmental changes on migratory flow.


With radar monitoring, we have gained insights in:

  • Influence of topographical structures (mountain ranges, sea, desert) on migratory behaviour
  • Elevational distributions of migrants in relation to atmospheric conditions (wind, etc.)
  • Flight speed, air speed and wingbeat patterns of wild birds
  • Composition of nocturnal bird migration (passerines, waterfowl)
  • Potential hazard for migratory birds by wind turbines and other tall buildings

Further information

We used national networks of weather radar to interactively map the spatio-temporal distribution of migratory birds. Enjoy exploring the maps!

Project partner(s)

Financial support



Other resources
TV report
On studying bird migration (in French)
Bird Migration link

Bird Migration

We research migratory birds from their breeding grounds to Africa and lay the foundations for their protection beyond national borders.

Learn more

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