|Copyright: Catherine Vincent (reggaetime) (46)|
|Date Taken: 2011-04-30|
|Exposure: f/7.1, 1/125 seconds|
|More Photo Info: [view]|
|Photo Version: Original Version|
|Date Submitted: 2011-05-19 22:24|
|[Note Guidelines] Photographer's Note [French]|
|Otters are semi-aquatic (or in one case aquatic) mammals. The otter subfamily Lutrinae forms part of the family Mustelidae, which also includes weasels, polecats, badgers, and wolverines. With twelve species in seven genera, otters have an almost worldwide distribution. They mainly eat aquatic animals, predominantly fish and shellfish, but also other invertebrates, amphibians, birds and small mammals.|
Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all except the sea otter have long muscular tails. The twelve species range in adult size from 0.7 to 1.8 metres (2 to 6 feet) in length and 5 to 45 kilograms (11 to 100 pounds) in weight.
They have a very soft, insulated underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water.
Many otters live in cold waters and have very high metabolic rates to help keep them warm. Eurasian otters must eat 15% of their body weight a day, and sea otters 20 to 25%, depending on the temperature. In water as warm as 10°C (50°F), an otter needs to catch 100 grams (3.5 oz) of fish per hour to survive. Most species hunt for three to five hours a day, and nursing mothers up to eight hours a day.
For most otters, fish is the staple of their diet. This is often supplemented by frogs, crayfish and crabs. Some otters are expert at opening shellfish, and others will feed on available small mammals or birds. Prey-dependence leaves otters very vulnerable to prey depletion.
Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the seas. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter does live in the sea for most of its life.
Otters are playful animals and appear to engage in various behaviors for sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups – in a few species these groups may be fairly large.
Only registered TrekNature members may rate photo notes.