Deer are accomplished swimmers. With their powerful hind legs and stamina, deer can swim at speeds up to 15 miles per hour. Additionally, the coat of a deer helps these mammals swim distances up to 10 miles. The deer undercoat is dense and woolly providing good insulation from the heat-draining effects of submersion in water. The long, hollow, air-filled hairs of the top coat provide buoyancy. These top hairs are so effective at assisting flotation that up to one third of the deer’s body can be above water while it is swimming.
Why do deer swim?
When frightened, panicked or to escape predators, deer will seek the safety of water. Deer will also swim to find food, shelter or isolated areas to give birth in areas inaccessible without crossing water. It is also suggested that deer may swim to get rid of ticks. However, it does not appear that there is any significant loss of ticks in the water.
For nearly a half hour I watched these two mule deer (Odocoileus hemionus) in Eagle Lake (near the Christie Day Use Area/Lassen County CA). There were no other people around. The deer walked about in the water for several minutes before beginning to swim. They did not go anywhere, simply swam back and forth and in circles for nearly twenty minutes. Eventually the deer returned near the shore and began to slowly wander off, never leaving the water. I believe that these mule deer were simply enjoying a “recreational” swim.
Regardless of their motivation, it was enjoyable to watch these two mule deer seemingly enjoy their time in the water with no apparent motivation. At the risk of anthropomorphization, I think these mule deer were simply having fun.