Typically, for some unknown reason, Ambulocetus is illustrated as a slick creature. However, as a mammal that has not quite yet dedicated its life completely to living in the water, it is hard to think that these creatures would have been entirely devoid of hair. They may have been less furry than this pair seen here, but they must have had some sort of hair. Regardless, fish was most likely on the menu as it appears to have been here. The whiskers I could actually see being relevant to the swamp life that has been hypothesized for Ambulocetus. In the dark silty waters of a swamp, the feeling powers of the whiskers would have been very beneficial for a large predator like Ambulocetus. It would also be very much like the apparatus seen in otters, muskrat, and beavers, as well as other river/pond/swamp dwelling mammals.