I only have access to the abstract and a brief write-up in New Scientist, but this paper in the journal Animal Cognition has caught my attention:
It has long been known that cetaceans and certain other sea mammals occasionally pop their heads out of the water to survey the surroundings. Does this mean that the animals can use a starry night sky to find their way around?
Apparently so, says a group of marine biologists led by Björn Mauck at the University of Southern Denmark in Odense. Mauck and his colleagues studied the behaviour of harbour seals (common seals) in a specially built pool covered with a dome onto which was projected a simulation of the northern sky. The researchers found that even when the artificial sky was rotated at random, the seals could home in with very high accuracy on a particular star defined with a laser pointer.
“Seals and many other animals are exposed to the starry sky every clear night, and thus certainly have sufficient opportunities to learn the patterns of stars,” says Mauck.
Actually, they have far more opportunities than most human beings, living as the latter do in urban areas with light pollution blocking out all but the brightest stars and planets.
To me the result of this study is not at all surprising, but still I feel a sense of wow! at having the stellar navigation hypothesis confirmed in this way. It would be interesting to see a larger scale study of other intelligent sea creatures such as migrating whales and their stellar navigation techniques. Just how this could be done I have absolutely no idea.