Magnetotactic bacteria orient and migrate along geomagnetic field lines. Magneto-aerotaxis increases the efficiency of respiring cells to efficiently find and maintain position at a preferred microaerobic oxygen concentration. Magneto-aerotaxis could also facilitate access to regions of higher nutrient and electron acceptor concentration via periodic excursions above and below the preferred oxygen concentration level.
Richard B. Frankel, Timothy J. Williams, and Dennis A. Bazylinski. "Magneto-Aerotaxis" Biology Monographs: Magnetoreception and Magnetosomes in Bacteria 3 (2007): 1-24.
Available at: http://works.bepress.com/rfrankel/102