Journal of Comparative Physiology A

, Volume 203, Issue 6–7, pp 491–497 | Cite as

The magnetic map sense and its use in fine-tuning the migration programme of birds

  • D. Heyers
  • D. Elbers
  • M. Bulte
  • F. Bairlein
  • H. Mouritsen
Review

Abstract

The Earth’s magnetic field is one of several natural cues, which migratory birds can use to derive directional (“compass”) information for orientation on their biannual migratory journeys. Moreover, magnetic field effects on prominent aspects of the migratory programme of birds, such as migratory restlessness behaviour, fuel deposition and directional orientation, implicate that geomagnetic information can also be used to derive positional (“map”) information. While the magnetic “compass” in migratory birds is likely to be based on radical pair-forming molecules embedded in their visual system, the sensory correlates underlying a magnetic “map” sense currently remain elusive. Behavioural, physiological and neurobiological findings indicate that the sensor is most likely innervated by the ophthalmic branch of the trigeminal nerve and based on magnetic iron particles. Information from this unknown sensor is neither necessary nor sufficient for a functional magnetic compass, but instead could contribute important components of a multifactorial “map” for global positioning. Positional information could allow migratory birds to make vitally important dynamic adaptations of their migratory programme at any relevant point during their journeys.

Keywords

Magnetoreception Navigation Orientation Migratory restlessness Migratory fuelling 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.AG Animal Navigation, Faculty of Biology/Environmental SciencesUniversity of OldenburgOldenburgGermany
  2. 2.Research Centre for Neurosensory SciencesUniversity of OldenburgOldenburgGermany
  3. 3.AG Biochemistry, Faculty of Medicine/Health SciencesUniversity of OldenburgOldenburgGermany
  4. 4.AugsburgGermany
  5. 5.Institute for Avian Research “Vogelwarte Helgoland”WilhelmshavenGermany

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