Fin Whales - Greyhounds of the Sea - 20 Knots Easy

CERSI, based in Sept-îles, reports: Two fin whales were seen swimming a linear trajectory in a synchronized manner, one behind the other. Swimming powerfully and rapidly, the animals dived for only short periods just beneath the surface. Their heads and blows created an explosive noise each time they surfaced. The two fin whales maintained formation for 10 breathing sequences out of 12: one behind the other, with the lead animal slightly to the right. The research team was not able to track the whales for very long; they covered two nautical miles in six minutes at a speed of 20 knots (37 km/hr).

Source: http://www.whales-online.net/eng/FSC.html?sct=1&pag=1-1-1.html