title: Migratory Reed Warblers Need Intact Trigeminal Nerves to Correct for a 1,000 km Eastward Displacement.
abstract: Several studies have shown that experienced night-migratory songbirds can determine their position, but it has remained a mystery which cues and sensory mechanisms they use, in particular, those used to determine longitude (east-west position). One potential solution would be to use a magnetic map or signpost mechanism like the one documented in sea turtles. Night-migratory songbirds have a magnetic compass in their eyes and a second magnetic sense with unknown biological function involving the ophthalmic branch of the trigeminal nerve (V1). Could V1 be involved in determining east-west position? We displaced 57 Eurasian reed warblers (Acrocephalus scirpaceus) with or without sectioned V1. Sham operated birds corrected their orientation towards the breeding area after displacement like the untreated controls did. In contrast, V1-sectioned birds did not correct for the displacement. They oriented in the same direction after the displacement as they had done at the capture site. Thus, an intact ophthalmic branch of the trigeminal nerve is necessary for detecting the 1,000 km eastward displacement in this night-migratory songbird. Our results suggest that V1 carries map-related information used in a large-scale map or signpost sense that the reed warblers needed to determine their approximate geographical position and/or an east-west coordinate.
authors.affiliation: Arbeitsgruppe "Neurosensorik/Animal Navigation", Institut für Biologie und Umweltwissenschaften & Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany.
authors.forename: Dmitry
authors.initials: D
authors.lastname: Kishkinev
authors.forename: Nikita
authors.initials: N
authors.lastname: Chernetsov
authors.forename: Dominik
authors.initials: D
authors.lastname: Heyers
authors.forename: Henrik
authors.initials: H
authors.lastname: Mouritsen
mesh_terms: D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D005843:Geography; D009949:Orientation / Q000502:physiology; D020308:Songbirds / Q000502:physiology*; D014276:Trigeminal Nerve / Q000502:physiology*