Sea Otter, a highly specialized marine mammal

Physically similar to a bear, only smaller, sea otter spends its whole life in the water. Swimming, feeding, and hanging out freely with families and friends. This animal inhabits coastal environments, where it dives to the seabed to forage. Sea Otter or the scientific name Enhydra lutris, typically have a lifespan between 15 and 20 years. Having adorable features, this animal can spend its entire life without leaving the water, forming a single-sex raft with its shady round eyes looking at the sky and hind feet resurface half from the water. The group of sea otters floating in the ocean is called rafts. The largest raft ever seen contained over 2000 sea otters floating on the water. They often hold their paws when sleeping to avoid drifting. Other than that, they also wrap themselves with kelp to avoid drifting. Sea otter is a member of the family Mustelidae comprises 13 other otter species like weasels, badgers, and minks. This North Pacific Ocean native animal can weigh between 14 kg to 45 kg, a typical children’s weight that makes them the heaviest members of the weasel family. Though, they are still known as one of the smallest marine mammals around the world. This mammal feeds on marine invertebrates like sea urchins, mollusks, crustaceans, and fish. The act of sea otter needing a tool (a rock for example) to eat and dislodge prey also to open shells is considered unique and intelligent. Despite their small size, one interesting fact about sea otters is that they are heavy eaters. They need to eat between 25 to 40 percent of their body weight every day. With this, sea otters feed on more than 100 varied species daily.  

Sea otters are known for their hygiene; their fur needs to be constantly cleaned all the time. Once their fur becomes dirty, they will have a problem absorbing the air to keep them warm and cozy. Hence, sea otters are obsessive in keeping their fur clean. They always groom their fur whenever they are not sleeping or hunting. They groom the fur on their faces by rubbing their faces with their paws, untangling, and removing loose fur during their free time. People may find them scratching but they actually blow air into the fur. Sea otters often roll in the water when eating to wash off any food waste on their fur.

Meanwhile, oil spills become a major problem for sea otters and usually end up with mortality. Sea otter suffers from the greed of humans in collecting their fur and meat. Its fur is the densest fur of any animal on Earth. It is approximately 1 million hair per square inch to keep them warm as sea otter does not have blubber. The fur is long comprising a waterproof shield that keeps the short underfur layer always dry. Between the fur, there is an air compartment to trap heat and warmth to the body, in which way no freezing water can enter the skin. Consequently, they were hunted for their fur historically between the year 1741 to 1911, and the world population fell drastically to 1000 to 2000 individuals living a fraction of their historic range.

Sea otters often close their nostrils and small ears by adapting to their surroundings. Most of the swimming activities of sea otter are done by the hind feet, a long, broadly flattened and fully webbed. The toes make it easier to swim but it is not made for walking, luckily the tail is short, flattened, and muscular, so it will not be a burden when moving from one place to another. They can move up to 9 km/h. Their bodies elongated to streamlined figures when swimming in the water and using their back when floating. Sea otters have tough pads on the palms functioning as a grip when catching prey. In addition, paws also have short retractable claws that give a good grip. The whiskers and front paws are extremely sensitive to touch which make it boundless when finding prey in dark or murky waters. The sense of smell is much more important to sea otter compared to sighting. This diurnal mammal has a period of foraging and eating in the morning like having breakfast before sunrise, and sleeps at midday. They will come back to forage in the afternoon before sunsets and the last meal will be at midnight. They frequently dive in shorts but deep down to the sea floor. They can hold their breath for up to five minutes long although the dives typically take not more than four minutes. Only a few people know that sea otter has a loose pouch of skin that extends across the chest. It usually functions as storage to keep food or rocks for tool.

Sea otters most likely will breed whenever a male sea otter marks and maintain a breeding territory that is favored by females. Males usually do the marking from spring to autumn as this is considered the highest breeding session. Females freely move around from one territory to another territory finding the best partner to mate. Males that do not have any place tend to involve in large, male-only groups, and swim through female areas to find a mate. They are considered polygynous; males have multiple female partners. Mating takes place in the water and can be violent towards the females. Males basically bite females on the muzzle leaving scars. Birth takes place in the water and produces a single pup weighing 1.4 to 2.3 kg. A pup has a thick coat of baby fur with open eyes and ten visible teeth. Mothers will lick and fluff a newborn for hours to retain air so that they will not sink in the water and consistently float. Females perform all parts of motherly tasks from feeding to raising offspring and sometimes caring for orphaned pups. The devotion of female sea otter can be seen when they carried a dead pup for days. Sea otters may seem playful and sociable, but they appreciate alone time. Distressed sea otters will whistle, hiss or in extreme circumstances, scream. Whereas cry of a pup is like a gull.

Sea otter acts as keystone species of kelp. In the simplest words, no sea otter, no kelp forest, and no food. Sea otters hunting on sea urchins, a villain to kelp forest. As sea otter acts as critical ecological animals, it has been protected by the International Fur Seal Treaty since 1911, the Marine Mammal Protection Act (MMPA), and the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES). Nevertheless, more countermeasures are needed in the future to fully protect this unique animal.