All in all, the sea otter preys on at least different marine species. Learn more: What do beavers eat in the wild? They have a unique foraging habit because they use rocks to kill their prey. Thus, the sea otter is one of the very few mammals to make an effective use of tools the other mammals are primates and perhaps the only aquatic mammal to pick up rocks and catch fish by means of its forepaws. There is a unique skin pouch below its forelegs and across the chest.
Sea otters eat a wide variety of prey, including marine invertebrates such as echinoderms sea stars and sea urchins , crustaceans e. Sea otters obtain their food by diving. Using their webbed feet, which are well adapted for swimming, sea otters can dive more than feet and stay underwater for up to 5 minutes.
Sea otters can sense prey using their whiskers. They also use their agile front paws to find and grasp their prey. Sea otters are one of the only mammals that are been known to use tools to obtain and eat their prey. They can use a rock to dislodge mollusks and urchins from the rocks where they are attached. Once at the surface, they often eat by placing the food on their stomachs, and then placing a rock on their stomachs and then smashing the prey on the rock to open it and get at the flesh inside.
Individual otters in an area seem to have different prey preferences. A study in California found that among an otter population, different otters specialized in diving at different depths to find different prey items. There are deep-diving otters that eat benthic organisms such as urchins, crabs, and abalone, medium-diving otters that forage for clams and worms and others that feed at the surface on organisms such as snails.
These dietary preferences may also make certain otters susceptible to disease. It also uses a flap of skin located under each foreleg to hold food temporarily while hunting until it returns to the surface.
Range Sea otter is found along coastal areas of the northern Pacific Ocean and the southern Bering Sea. Three separate sub species live along the coasts of Russia, Alaska, and California. Reintroduced populations in British Columbia and Washington state. Habitat Found in marine habitats with rocky or muddy sea bottoms and is frequently associated with kelp forests. Rarely ventures onto land. Females give live birth to, normally, one pup at a time.
Pups remain dependent upon their mothers for approximately six months. Their lives are usually longer in an aquarium or zoo setting. Reproduction During the mating season, the male bites the snout of the female in a display of courting behavior. Consequently, sexually mature females can be distinguished by bloody or scarred nose regions.
Female sea otter is pregnant for four-and-a-half months. Delayed implantation periods in sea otters depend on individual and geographic variation. It ranges from two to three months in southern sea otters and can last as long as eight months in northern sea otters.
Sea otter pup can emit a strong high-pitched call when in distress or separated from its mother. It is nursed by its mother for six months to a year, but can begin foraging in shallow water habitats as soon as six weeks after birth. Social Behavior It is believed that a sea otter will wrap itself with kelp before sleeping at the surface to keep itself from drifting away.
Southern sea otter is not a social animal as are other otter species and has been known to live alone. Sea otters are quite large, weighing up to pounds 45 kg and reaching lengths of nearly 5 feet 1. Both mating and birth take place in the water, and males have harems of several females.
Mothers nurse their young for up to eight months. When the mothers dive for food, they tie their babies into kelp to ensure that they will not float away. Unlike most marine mammals that rely on a thick layer of blubber to insulate them from cold ocean waters, sea otters rely on their extremely thick fur — the thickest of all animals.
In fact, sea otters have so many hairs per square inch that their skin never actually gets wet, even though they live their entire lives in the ocean. In the 18 th and 19 th centuries, sea otter pelts were highly valued for their use in making coats and other outerwear, and the species was nearly hunted to extinction.
Scientists estimate that the total population reached levels less than one percent of their pre-hunting numbers. Sea otters now have legal protection throughout much of their range, and there has been some recovery in recent decades. However, scientists still believe that populations are decreasing as a result of oil pollution, changes to north Pacific food webs, and habitat loss, and this species is considered endangered highly vulnerable to extinction.
Without continuing conservation measures and legal protection, this charismatic species could be at risk of being lost forever. Sea otters reach maximum lengths of 4.
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