Fish Foods

©Florida Museum of Natural History

It has been determined, or rather hypothesized, that Enhydritherium had a mainly piscivorous, or fish-based, diet. This was based on the fact that Enhydritherium possessed bones in its front paws that are more similar to extant fish catching otters than to its ancestors which are thought to have lived on land and did not eat fish regularly. Modern fish catching otters use their mouths to catch their prey whereas the ancestors of Enhydritherium used their hands to catch and grab food items; this means that the hands of Enhydritherium and modern otters are not as adept at grasping and handling food items as their ancestors. Enhydritherium also possessed large attachments for neck biting muscles and, as a direct relation, probably had extremely large and powerful neck muscles. These would have been used to attack prey quickly and hold them as the otter then left the water to secure and feed on its fish prey. These neck and biting muscles were very important for Enhydritherium because it was not capable of chasing its food in the water. Poor swimming adaptations in the hindlimbs made Enhydritherium good at wading into water and escaping from the water, but unable to chase aquatic prey. The hindlimbs of the animal were much more adapted to terrestrial locomotion. As such, it was capable of long overland journeys like that which Tseng, et al. 2017 describes as a hypothesis of migration between the bicoastal populations of Enhydritherium.