Modelling migration: the clock-and-compass model can explain the distribution of ringing recoveries

Area of Science:

• Ornithology
• Animal Behavior
• Navigation

Background:

• Bird migration is a complex phenomenon involving navigation over long distances.
• Understanding the orientation mechanisms used by migratory birds is crucial for conservation efforts.

Purpose of the Study:

• To investigate if a simple clock-and-compass strategy explains the directional distributions observed in bird migration recoveries.
• To test the hypothesis that night-migrating passerines rely on basic orientation mechanisms.

Main Methods:

• Development of a mathematical model predicting directional distributions based on a clock-and-compass strategy.
• Comparison of model predictions with empirical ringing recovery data of pied flycatchers (Ficedula hypoleuca) from Scandinavia.

Main Results:

• Model predictions showed a strong correlation with the observed distribution of pied flycatcher ringing recoveries.
• The findings support the use of a simple clock-and-compass strategy in autumn migration.

Conclusions:

• Young pied flycatchers, and potentially other night-migrating passerines, utilize a straightforward clock-and-compass system for migration.
• This suggests that known orientation prerequisites, a compass and internal clock, are sufficient for migration, negating the need for advanced navigational abilities or a map sense.