Archives: Otter Species

If you give an otter a piece of fish, the otter will reach for it with its mouth. Give a small-clawed otter a piece of fish and it will grab it in its hands! An extremely dextrous animal with reduced claws (hence the name) and diminished webbing between the fingers, this otter is probably the most charismatic in the world. Like its close cousin the smooth-coated otter, it is very social, forming dynamic, playful family groups. They form lifelong monogamous pairs and are very adaptable, living in fast flowing waters in Thailand, pools of stagnant water in West Java, swamps, rice paddies, peat and mangrove forests. During their foraging trips they wander further from the water than other Asiatic species, looking for crabs, along with snails, molluscs, insects and small fish. Sometimes seen in large groups of up to 20 individuals, the crab-eating otters are seen as an asset by local rice farmers since crabs are considered a pest in rice paddies.

A close cousin to the small-clawed otter, the smooth-coated otter has a large distribution that is slowly but steadily shrinking, a fact made obvious by the remnant of a population in Iraq – its range once spread from the Middle-East to southeast Asia. Its problem is and has always been its biggest asset: a short, smooth, velvety fur, warm chocolate brown on the back and soft grey on the stomach. These otters are mainly nocturnal, although they can be diurnal when unmolested. Smooth-coated otters form large, vocal, family groups, preying together on fish, shrimps, frogs, crabs, insects, birds. Found mainly in the slow flowing waters typical of rice paddies and floodplains, they may use large rivers in some regions. The smooth- coated otter needs thick riverside vegetation in which to hide, dig dens and raise cubs. Recently, illegal trapping for the fur trade has taken a heavy toll in many Asian countries in which this species occurs and law enforcement is lacking.

The hairy-nosed otter is easily recognizable by its hairy nose pad and white upper lip. This otter is considered a miracle otter: having been declared extinct in 1998, this small, elusive otter was recently and with great excitement rediscovered in Vietnam,Thailand, Malaysia, Indonesia, Borneo and Cambodia, mostly thanks to camera trap evidence. Individuals killed on roads and sighted in the wild are popping up in seemingly disconnected locations in southeast Asia, evidence that the hairy-nosed otter is still, albeit precariously, present and largely unknown. Based on the contents of recovered scat, its diet seems composed predominantly of fish, but it also eats water snakes, frogs, lizards, terrapins, crustaceans and insects that live in swamps and shallow coastal waters. It is so rare and the risks to its survival so elevated that ex-situ conservation methods are being considered – mainly capturing individuals for reproduction in captivity and the chance of a future restocking of nature reserves.

The spotted-necked otter is easily recognised thanks to the distinctive white patches on its upper lips and/or neck. Not all individuals show lip markings or a spotted neck with some exhibiting just a few neck flecks or none at all. Unlike the two other sympatric African species, the spotted-necked otter is slim and has webbed paws, reduced whiskers and is diurnal in some areas. It specialises in hunting fish by sight in clear, deeper and flowing waters. This otter will also prey on frogs, crabs and small water birds and is more aquatic than the other African species. If there is enough prey, it will form large, social, all male or juvenile groups; two females with cubs have been known to form loose packs using the same core area simultaneously. It is famous for its strong inclination to play and has been seen playing with other otters and alone; the cubs are very dependant and may stay with the mother for up to two years. Introduced fish species, such as the Nile perch, are a thought to be a threat to the spotted-necked otter because they tend to be too large and fast for the otter to catch and, being more aggressive, are pushing the smaller, local species to the brink of extinction, potentially leading to a decrease in the otters’ preferred food supply. Check out our sister group, the African Otter Network, for more info on our projects regarding African otters.

Nearly as large as the Cape clawless otter but definitely lighter and more slender, the Congo clawless otter was thought to be a subspecies of the former Cape clawless otter until recently. Little is known about this otter, which is the least studied of the African species. Its reduced whiskers, absent webbing, tiny claws and generalised dental morphology together with sporadic observations show that this species is mainly terrestrial, exploring marshes and forests. It uses its fingers to dig up molluscs, crabs, earthworms and frogs from the muddy banks. The Congo clawless otter’s head and neck is frosted with a brilliant white, that make its characteristic black markings under the eyes even more evident. Solitary, enigmatic and elusive, the Congo clawless otter still has many mysteries to reveal! Check out our sister group, the African Otter Network, for more info on our projects regarding African otters.

The Eurasian otter is an elusive, solitary otter that has one of the widest distributions of all palearctic mammals, from Ireland to China and down to SoutheastAsia.Notwithstanding its large range,its population is declining in many countries in which it is not protected and in others its status is unknown. This species has made a spectacular comeback in the British Isles since the 1980s when pollution levels decreased and it became protected.This playful otter has a varied diet which includes fish, crustaceans, amphibians and sometimes reptiles, birds, eggs, insects and worms. It is usually nocturnal and can be found in many freshwater environments. In some environments, however, such as the Scottish Isles, it has diurnal habits and forages in the sea, later looking for freshwater pools to wash the salt out of its pelt. The Eurasian otter is solitary, but sometimes it is seen in family groups, composed of a mother and her offspring.

The North American river otter is a large otter whose story is a success. By the 1950s its numbers were greatly reduced due to trapping and pollution, but after a long campaign to clean the waterways, trapping management and reintroductions in states in which it no longer occurred, this species now thrives throughout the USA and Canada. Renowned for their playfulness, North American river otters are active year round, even in deep snow.They are mainly crepuscular and eat fish, molluscs and crustaceans while other sources of food are consumed opportunistically. More social than Eurasian otters, they are commonly seen in small family groups of mothers and their offspring and that may include year-old individuals known as “helpers”. They build their dens in river banks and line them with leaves, moss, grass, bark and hair.

A top favourite, the sea otter is the international ambassador species for otters, being the first to have been nearly hunted to extinction and saved in the nick of time. Unlike other marine mammals, they have no blubber to protect them from hypothermia. Instead, they have the thickest, densest fur of all mammals: 500,000 hairs per square centimetre! It was this feature that made its fur so desirable and nearly caused this otters’ demise. Although sea otters have made a remarkable recovery in Alaska and the Northeast Pacific, they are still in danger from predators like orcas, poachers, and water-borne toxins that are increasing due to warmer water temperatures. Sea otters are social and live in single sex groups, unlike other otter species. They rarely come ashore but float instead, diving for clams, crabs, and urchins.

The largest extant otter species in the world is the giant otter from South America. Nearly hunted to extinction, it can reach up to 170 cm in length and lives in large, social family groups that sleep, play and hunt together. Typically, a monogamous pair that mates for life is at the head of the group composed of their offspring. They are vocal and territorial and although they will actively defend their home from intruders, some instances of acceptance of new, unrelated individuals to the group have been recorded. Being diurnal, noisy and living in groups, the giant otter is relatively easy to see in areas in which it is protected and is very popular with ecotourists. Its latin name, Pteronura, refers to its flat, winglike (ptero) tail (nura), which is one of the giant otter’s distinctive features, along with the markings on its neck that are used to identify individuals.