ArticleScientific reports2016
Migratory blackcaps can use their magnetic compass at 5 degrees inclination, but are completely random at 0 degrees inclination.
Article in Scientific reports, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
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Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Directionality range in Emlen funnels.Journal of the Royal Society, Interface · 2026Pooled it
- A magnetotactic bacterium capable of magnetic sensing.iScience · 2025Article
- Do first-time avian migrants know where they are going: the clock-and-compass concept today.Frontiers in physiology · 2025Review
- Migratory birds can extract positional information from magnetic inclination and magnetic declination alone.Proceedings. Biological sciences · 2024Article
- Adaptive evolution and loss of a putative magnetoreceptor in passerines.Proceedings. Biological sciences · 2024Article
- Morphology, biochemistry and connectivity of Cluster N and the hippocampal formation in a migratory bird.Brain structure & function · 2022Article
- In Search for the Avian Trigeminal Magnetic Sensor: Distribution of Peripheral and Central Terminals of Ophthalmic Sensory Neurons in the Night-Migratory Eurasian Blackcap (Frontiers in neuroanatomy · 2022Article
- Modelling collective navigation via non-local communication.Journal of the Royal Society, Interface · 2021Article
- Protein-protein interaction of the putative magnetoreceptor cryptochrome 4 expressed in the avian retina.Scientific reports · 2020Article
- Magnetoreception in birds.Journal of the Royal Society, Interface · 2019Review
- Lidocaine is a nocebo treatment for trigeminally mediated magnetic orientation in birds.Journal of the Royal Society, Interface · 2018Article
- Review
- A light-dependent magnetoreception mechanism insensitive to light intensity and polarization.Journal of the Royal Society, Interface · 2017Article
- Compass systems.Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology · 2017Article
- Route simulations, compass mechanisms and long-distance migration flights in birds.Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology · 2017Review
- The magnetic map sense and its use in fine-tuning the migration programme of birds.Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology · 2017Review
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Authors and funding
8 authors.
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No grant is acknowledged in the PubMed record.
Abstract
It is known that night-migratory songbirds use a magnetic compass measuring the magnetic inclination angle, i.e. the angle between the Earth's surface and the magnetic field lines, but how do such birds orient at the magnetic equator? A previous study reported that birds are completely randomly oriented in a horizontal north-south magnetic field with 0° inclination angle. This seems counter-intuitive, because birds using an inclination compass should be able to separate the north-south axis from the east-west axis, so that bimodal orientation might be expected in a horizontal field. Furthermore, little is known about how shallow inclination angles migratory birds can still use for orientation. In this study, we tested the magnetic compass orientation of night-migratory Eurasian blackcaps (Sylvia atricapilla) in magnetic fields with 5° and 0° inclination. At 5° inclination, the birds oriented as well as they did in the normal 67° inclined field in Oldenburg. In contrast, they were completely randomly oriented in the horizontal field, showing no sign of bimodality. Our results indicate that the inclination limit for the magnetic compass of the blackcap is below 5° and that these birds indeed seem completely unable to use their magnetic compass for orientation in a horizontal magnetic field.
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