Otter-ly fascinating

Last week’s unfortunate encounter between kayakers and a river otter on Braden River, where a woman got scratched when an otter jumped into her kayak, was an anomaly. Their whimsical antics make otters a popular attraction wherever they are on display to the public. In the wild they are seldom seen, as they are naturally shy and avoid people. But as a rabies-vector species, they should always be treated with cautious respect when they are encountered.
Peace River Wildlife Center had the privilege of treating a juvenile river otter over the weekend. It had been found loping along beside a busy road with no mother in sight. The rescuer was careful not to handle the suspected orphan with his bare hands. He corralled the otter into a kennel and brought her to PRWC where we treated her for dehydration.
River otters are found throughout Florida except for the Keys. These animals have a huge range, and are indigenous from Mexico to Alaska. They are especially abundant in Canada. Otters are a member of the mustelid family, which includes other carnivorous mammals like weasels and skunks. They have thick, luxurious, water-repellant coats that help insulate them from heat loss while spending most of their time in and around the water. Their fur density has been estimated to be 58,000 hairs per square centimeter. An average human’s head has 100 hairs per square centimeter.
Their long, slender bodies and short legs with webbed toes make otters adept swimmers. Under water they have been clocked at 4 miles per hour, while they can swim up to 6 miles per hour on the surface. Adults weigh 10-30 pounds, with the males being slightly larger. The average lifespan in the wild is around 8 years, bit they can live over 20 years in captivity.
River otters prefer fresh water, although they can be found in brackish water and are often seen in local canals—and even sometimes in the shallows of Charlotte Harbor. Their diet consists predominately of fish, crayfish, crustaceans, and turtles. Their teeth are remarkably strong, enabling them to crunch through the shells of invertebrates.

Their high metabolic rate helps maintain their body temperature in an aquatic environment, but there’s a trade-off—they must eat 15% of their body weight every day. That is the equivalent of a 200-pound person eating 30 pounds of food daily. While that might not be much of a stretch for some people, I’d hate to have to pay the bill for that steak at Outback.
In Florida, otters give birth during the fall and winter, although mating activities may occur anytime. The embryos develop over 8 weeks, but gestation can take up to 11 months. This incongruity is the result of delayed implantation. The fertilized egg can wait many months in a state delayed development, before seasonal changes trigger the implanting in the female’s uterus and continuation of the pregnancy.
Otters den in river banks, usually taking over a burrow made by another animal or a natural hollow formed by a fallen tree or root system. One to three pups are born fully furred, but blind and toothless. Their eyes open at four weeks and the babies are weaned by three months. The pups remain in a group with their mother for a year. They are social animals and are notorious for their playful antics as they learn how to hunt.
It is important to raise juveniles with others of their own species so that they learn appropriate behaviour, ensuring a full and happy life once released back into the wild. Wildlife Center of Venice has two other young otters and better facilities for raising this species than PRWC, so our baby was transferred there.
Wildlife Center of Venice has undergone a transformation in the past few months. They have purchased property near their old facility and are in the process of moving their operation there. Not having educational displays is both a blessing and a curse for them. They have more room to dedicate to rehabilitation caging and habitats, but without public visitations, it is more difficult to raise money. WCV, like PRWC, receives no federal or state funding, and relies solely on the support of donors to provide services to the public.
Pam DeFouw is the new director of operations at WCV, and she will be sharing this column with me going forward. She has been with WCV since 2012 and is looking forward to taking the organization in a bold new direction. “We will really miss co-founder Kevin Barton as he leaves to pursue other interests, but our goal is to continue the work he so tirelessly started. We want to make him proud.” I’m sure they will.
by- Robin Jenkins, DVM