Bobolink (Dolichonyx oryzivorus) Science Article 3
The bobolink (Dolichonyx oryzivorus) uses the earth’s magnetic field as one source of directional information for its migratory orientation. However, the location and structure of the magnetoreceptors that transduce the magnetic information to the nervous system are unknown. Because treatment with a strong magnetic pulse results in a change in the direction of orientation, one of the receptors is thought to involve a magnetizable material such as magnetite.
ROBERT C. BEASON AND PETER SEMM, The Journal of Experimental Biology 199, 1241-1244 (1996)