The North American Otter, "Lutra Canadensis", is the fastest mammal in the freshwater lakes and rivers of their habitat. Cruising along at six miles an hour it can stay under water for over 4 minutes and can swim a quarter of a mile submerged before coming back up for air!
Otters are excellent fishers. They are capable of killing a fish up to 20 pounds in weight, although normally their quarry is much smaller. They have been known to hunt for trout but prefer easier prey such as the Sunfish and other slower varieties.
Hunting mainly at night, they are opportunist predators who will concentrate on the fish that keep to the intertidal and sub tidal regions close to the shoreline. They use their very sensitive whiskers to detect moving prey and then their keen sense of touch will enable them to catch the fish with their paws and rip it apart with their teeth. They are also not averse to varying their diet occasionally and relish the odd duck, musk rat or young beaver. Smaller meals are quickly consumed whilst still in the water and the larger and more cumbersome meals are pulled up onto land.
Otters are fastidious creatures and will clean themselves up after each meal and roll around to dry themselves off. They must groom themselves constantly to maintain the insulating qualities of their fur and many species of otter will keep special places on the shore purely for grooming and drying their fur.
With its lithe, muscular body, broad, flat head, small ears and long, powerful tapering tail, the otter is beautifully streamlined for darting through water. It had short limbs but the hind feet are extremely large and strong and broadly webbed. The otter's rich brown coat is very oily and dense which helps to keep him warm in the cold water.
Otters are continuously moving around and will keep to a parameter of 20 miles, traveling a circuit of rivers and lakes over a 2 3 week period. If the fishing is particularly good they may stay put for a while but never for any length of time.
Otters are highly engaging creatures but unfortunately their affability towards man has been their undoing. For many years they were hunted for their valuable fur but with successful conservation projects their numbers have increased.