So instead , they dropped the pup in with the female otter, and she immediately went into mom mode. The aquarium has since devised a system of hand-rearing pups for the first six to eight weeks—mostly for bottle feeding purposes—before handing the pups off to female otters for raising. At six months, the pups are released back into the wild with generally strong results. Otters can have up to one million hairs per square inch. There are two layers of fur—an undercoat and then longer hairs that we can see.
The layers manage to trap air next to the otter's skin, which keeps the otters dry and warm and also helps with buoyancy. Otters love to eat shelled animals, like clams, but they aren't equipped with the strength to open their food without some help. Therefore, they are big on tools and will often use rocks to help crack into dinner.
Some tribes consider the otter to be a lucky animal and a symbol of "loyalty and honesty. Some cultures even forbid eating the creatures and were offended when colonial Europeans began hunting the river otters and selling their furs. In , a study of giant otters found that the river-dwellers have 22 distinct noises they make for different situations.
On top of that, pups have 11 of their own calls that they intersperse with "infant babbling. In Bangladesh, otters help fisherman maximize their haul. For centuries, fisherman have been training otters to act as herders and chase large schools of fish into the nets. Keeping an eye on otters in the wild is a tricky task. In the past, observers have usually set up telescopes on shore to try and monitor otters at sea. Otters won't act naturally with humans nearby, and using a telescope on a boat can get tricky in the rollicking ocean.
But now, scientists are using unmanned drones with cameras to get an aerial look at otters in their element, making it easier to monitor the creatures as they dive for food and go about their day. Or a family or a raft. Otter groups go by a few different monikers, all of which are fairly unique to that crew. Don't challenge an otter to a holding-your-breath competition! Sea otters can stay underwater for 5 minutes, and river otters can hold their breath for even longer - 8 minutes!
Otters like to stick together, so when they sleep they will wrap themselves in seaweed and float together in a group. A group of resting otters is called a raft. We wouldn't go drifting away on one of these rafts, however! Otters have a nasty bite! Log out. Habitat loss and pollution played a major part in the decline. But habitat loss and hunting have brought many populations of other otter species crashing down around the world, especially in more tropical locations.
North American sea otters are something of a recent success story after they were brought close to extinction in the 19th century, widely hunted for their fur. This was stopped by the establishment of the International Fur Seal Treaty in Populations in Canada and California are now doing well.
Otters have their cubs in underground dens called holts, which they dig themselves. They will also use hollows under trees or old rabbit holes. Their droppings are known as spraints and can be identified by an odour that is said to range from musky mown hay to jasmine tea to rotting fish.
It is made up of a waterproof top layer and a short underlayer, which can contain as many as one million hairs per square inch. This makes up for its lack of blubber in the cold Pacific water. Even a baby sea otter can stay warm on the open ocean, but they do need some help from their mothers. Winter brings many challenges for Eurasian otters. The species has no seasonal fur variation, so expends far more heat and energy swimming and diving in colder waters despite its dense, double-layered coat.
Scottish coastal otters, for example, which usually forage and hunt throughout the day in summer, instead seek prey more intensively in the mornings though, interestingly, camera-traps set by the International Otter Survival Fund have revealed that they are in fact also active at night.
Winter brings many other dangers to otters. If conditions are mild and wet, cubs can drown in flooded holts. Swollen, murky waters also make swimming more difficult, forcing the animals onto busy roads. This species is the most widely distributed of all the otters, ranging through Eurasia up to the Arctic Circle, from Ireland to Kamchatka, and south to North Africa, Sri Lanka and Indonesia.
Their varied and adaptable diets mean they may inhabit any unpolluted body of fresh water, including lakes, streams, rivers, and ponds, as long as there are adequate food supplies. On the Shetland Islands, some otters have been known to abandon fishing in favour of rabbit hunting. Extremely few individuals survive in Vietnam, southern Thailand, Sumatra and Cambodia, mainly due to poaching. It is one of the rarest otter species. Until , it was thought to have been extinct, but small populations have been discovered since then.
Until recently, the spotted-necked otter was considered to be part of the Lutra genus, but it is now placed in the Hydrictus genus.
It is common in Lake Victoria and Zambia, but not in some lakes and rivers, such as in the Zambezi below the Victoria Falls. An isolated population of the species is also found in the marshes of Iraq indicating the range must once have been wider.
The fur of this species is smoother and shorter than that of other otters, and they use scent to communicate both within the otter species, and with other animals. In the past, this species was widely employed throughout its range by fishermen, with trained animals being highly valued. Due to trapping, water pollution and habitat degradation, the numbers of North American river otter had declined through most of their range by the early s.
The South American river otter can be found in marine, freshwater, and terrestrial habitats throughout Chile and Argentina. This species has the widest distribution of all the Lontra species, from northern and central Argentina up through south and central America to northwest Mexico.
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