Yes. There is evidence that some animals, probably most notably sea turtles, have the ability to sense the Earth's magnetic field (although probably not consciously) and to use this sense, along with their several other senses, for purposes of orientation. We acknowledge that this is an interesting subject, and inquisitive acquaintances have posed this question to us on many occasions. However, the issue of magnetic orientation by animals is really more a matter of biophysics rather than geophysics, and we will, therefore, refer the curious reader to the following authoritative articles:

• Lohmann, K. J., Hester, J. T. & Lohmann, C. M. F., 1999. Long-distance navigation in sea turtles, Ethology Ecology & Evolution, 11, 1-23.
• Skiles, D. D., 1985. The geomagnetic field: Its nature, history and biological relevance, In Magnetite Biomineralization and Magnetoreception by Living Organisms: A New Biomagnetism, Ed: Kirschvink, J. L., Jones, D. S. & MacFadden, B. J., Plenum Publishing Corporation, New York.
• Walker, M. M., Dennis, T. E. & Kirschvink, J. L., 2002. The magnetic sense and its use in long-distance navigation by animals, Current Opinion in Neurobiology, 12, 735-744.
• Wiltschko, R. & Wiltschko, W., 1995. Magnetic orientation in animals, Zoophysiology, 33, Springer Verlag, Berlin.