MA'OR YESHIVA HIGH SCHOOL of the Jersey Shore Celebrating 10 Years of Educational Excellence
The sea otter is the smallest mammal in the marine world and is native to the northern and eastern coasts of the Pacific Ocean. Despite being the smallest aquatic mammal, the sea otter is the largest member of the weasel family. It can reach five feet in length and weigh up to 100 pounds.
The fur of the sea otter can range from brown to almost black, with guard hairs (long, coarse hairs that cover and protect the soft underfur of an animal) that may be black, light brown, or silver. The sea otter has a long, flat tail and webbed hind feet that allow it to swim efficiently in the water - which is vital, since the sea otter spends most of its life in the water. It is even able to close its ears and nostrils in the water, and can live in the water for its entire life, if necessary. But unlike other marine mammals like the whale, which cannot survive on dry land for too long, sea otters are able to walk onto land to rest, groom, or nurse.
Another difference between the sea otter and all other marine mammals is the fact that the sea otter does not have a layer of blubber to keep it warm. Instead, it relies on its dense fur to keep the cold out. The sea otter is known to have one of the thickest, warmest coats of fur in the whole animal kingdom. This coat helps keep the sea otter warm in the cold waters of the North Pacific. Its fur consists of two layers: a waterproof layer of long guard hairs, and a layer of short, thick fur underneath that. Air around the fur is heated by the sea otter’s body heat, and this air in turn keeps the sea otter warm.
Sea otters are omnivores, as, aside from eating meat, they do eat seaweed and other aquatic plants. Most sea otters, however, have a primarily carnivorous diet and are known to eat many different species of marine animals. Although the sea otter is a very social creature, it hunts and forages for food alone. It primarily hunts sea urchins, clams, crabs, snails, and small fish in the water. The sea otter mainly stays near the surface of the water, but it will dive as far as 250 feetunderwater when hunting for food. The retractable claws on its front paws enable the sea otter to grab and hold onto its prey.
The female sea otter usually gives birth to one pup per year. Mother sea otters will nurse their pups for up to a year, at which time the sea otter pups are able to hunt and forage for food by themselves.
Sea otters can live up to twenty-five years.
The sea otter is the only marine mammal in the animal kingdom that has the ability to use tools. For example, the sea otter will use a rock to open a hard-shelled prey such as a clam or a mussel. In order to pry open the shell of its prey, the sea otter places the rock on its chest and then takes its prey and smashes it repeatedly against the rock until the shell breaks open. Keep in mind that all of this is happening while the sea otter is floating on its back in the water! Sea otters always eat in the water and never on land.
The fur of the sea otter is the finest of any mammal, consisting of 850,000 to 1,000,000 hairs per square inch. These hairs keep the sea otter warm while it is in the water.
Sea otters are meticulously clean. They spend hours each day grooming their coats, which includes cleaning their fur, untangling knots, removing loose hairs, rubbing their fur to squeeze out water, and blowing air into their fur. After eating, they wash themselves in the water frequently, grooming their fur with their teeth and paws. It is extremely important that sea otters keep their fur clean of dirt and debris, in order that it remains waterproof and able to insulate them against the cold. If the fur is covered with dirt or other substances, aircannot penetrate through the fur’s hairs, and the sea otter will get too cold.
The More the Merrier
Sea otters are very social animals and are often seen floating together in large groups, called rafts. Sea otter rafts can consist of between ten to over 100 sea otters. The largest recorded sea otter raft contained over 2,000 sea otters. Rafting sea otters will hold each other’s paws while sleeping, to avoid drifting apart from the group. These large groups of sea otters are usually separated by gender; females and their pups are in one group, while the males float in their own group.
The majority of sea otter pups are born in early spring. Newborn sea otters range in weight from three to five pounds. At birth, the pup’s eyes are open, it has a full coat of baby fur, and ten teeth are visible. The mother sea otter is a very devoted and nurturing parent, giving her pup constant attention. Besides being responsible for feeding and raising her young, the mother sea otter also grooms her pup to keep its fur clean and cradles the pup to keep it warm. When she needs to dive in the waters to find food for her young, she leaves the pup wrapped and secured in large seaweed.
After a few weeks, the young sea otter should be able to swim, dive, play, groom itself, and eat solid foods. The young sea otter will leave its mother to live on its own between the ages of five to twelve months.