There are 12 species of otters worldwide. The mammal appears on every continent except Australia and Antarctica. The largest of the freshwater species is the giant otter of the Amazonian basin, weighing up to 66 pounds; the shorter but heavier sea otter of the north Pacific coastline can weigh up to 90 pounds. Throughout its range, otter populations are declining as a result of continued habitat loss and the harvesting of its meat and fur.
The only aquatic member of the weasel family, the otter is renowned for its playfulness. Curious and entertaining to observe, it is a favorite at zoos and aquariums. Children seem to gravitate to the otter naturally, as they do with the dolphin. In the wild, the otter is far less playful but is still known to slide down a muddy embankment repeatedly or engage in other behavior that can only be described as having fun. Aside from primates, the sea otter is the only mammal known to use tools when harvesting food.
The diet of the river otter is largely made up of fish, both fresh and saltwater species. It prefers slower-moving fish such as gar, panfish and catfish, but will catch just about any fish it can. It also eats crawfish, horseshoe crabs, frogs, coots, ducks, beetles and on rare occasions, muskrats and marsh rabbits.
An otter family at play.
PHOTO BY HEATHER GREEN
An otter is capable of holding its breath for up to four minutes, diving as deep as 60 feet and swimming as fast as six-miles per hour. Its fur is so dense that its skin never gets wet. Young otters, even though they are born with webbed feet and will eventually spend most of their lives in the water, must be taught how to swim by their parents. The otter is very vulnerable to water quality issues and will quickly abandon any polluted lakes or streams. Poor water quality has been a major factor in the otter's decline worldwide.
The river otter is slowly being reintroduced into states where it once was plentiful, including Iowa, Kansas, Kentucky, Nebraska, New Mexico, North and South Dakota, Ohio, Oklahoma, Tennessee and West Virginia. It was formerly found in all of these states, but over the past few centuries has been trapped for its high-quality fur, causing localized extinctions. Most states now protect the otter.
The otter is preyed upon by alligators, bobcats, coyotes, and wolves. Because of its unusual method of running, arching its back high into the air as it runs, it is very vulnerable to automobile collisions. Oil spills are especially troublesome for the otter. The Exxon Valdez spill in Prince William Sound killed more than 1,000 sea otters and dozens of river otters within days.
By and large the otter is a rare sighting. It is most often spotted in the early mornings and at dusk. Sadly, most of the otters we see are those who have been killed in automobile collisions. The best locations to find river otters are in areas with multiple freshwater ponds, where you can sometimes see them crossing over from one body of water to another. In Florida, where otters are protected, the species is making a strong come back. Many coastal otters were severely impacted by the 2004 and 2005 hurricane seasons and populations along the coast are currently lower than normal.
This is an excerpt from The Living Gulf Coast - A Nature Guide to Southwest Florida by Charles Sobczak. The book is available at all the Island bookstores, Baileys, Jerry's and your favorite online sites.