Migratory birds can extract positional information from magnetic inclination and magnetic declination alone

Packmor, Florian; Kishkinev, Dmitry; Zechmeister, Thomas; Mouritsen, Henrik; Holland, Richard A.

Abstract

Migratory birds are able to navigate over great distances with remarkable accuracy. The mechanism they use to achieve this feat is thought to involve two distinct steps: locating their position (the “map”) and heading towards the direction determined (the “compass”). For decades, this map-and-compass concept has shaped our perception of navigation in animals, although the nature of the map remains debated. However, some recent studies suggest the involvement of the Earth’s magnetic field in the map step. Here, we tested whether migratory songbirds, Eurasian reed warblers (Acrocephalus scirpaceus), can determine their position based on two magnetic field cues more commonly associated with direction-finding in birds, magnetic inclination and magnetic declination. During a virtual magnetic displacement experiment, the birds were exposed to altered magnetic inclination and magnetic declination values that would indicate a displacement from their natural migratory corridor, but the total intensity of the field remained unchanged. The response was a change in the birds’ migratory direction consistent with a compensatory re-orientation. This suggests that birds can extract positional as well as directional information from these cues. It remains to be seen whether birds use the total intensity of the field for navigation.

Citation

Packmor, F., Kishkinev, D., Zechmeister, T., Mouritsen, H., & Holland, R. A. (2024). Migratory birds can extract positional information from magnetic inclination and magnetic declination alone. Proceedings of the Royal Society B: Biological Sciences, 291(2034), https://doi.org/10.1098/rspb.2024.1363

• Journal Article Type: Article
• Acceptance Date: Oct 14, 2024
• Online Publication Date: Nov 13, 2024
• Publication Date: Nov 13, 2024
• Deposit Date: Nov 4, 2024
• Publicly Available Date: Nov 8, 2024
• Journal: Proceedings of the Royal Society B: Biological Sciences
• Print ISSN: 0962-8452
• Electronic ISSN: 1471-2954
• Publisher: The Royal Society
• Peer Reviewed: Peer Reviewed
• Volume: 291
• Issue: 2034
• DOI: https://doi.org/10.1098/rspb.2024.1363
• Keywords: magnetic compass, magnetic map, magnetoreception, bird navigation, map-and-compass concept, Eurasian reed warbler
• Public URL: https://keele-repository.worktribe.com/output/921495
• Publisher URL: https://royalsocietypublishing.org/doi/10.1098/rspb.2024.1363
• Additional Information: Accepted on 14th Oct as is after minor revision