Eurasian otter, Eurasian river otter, European river otter, Old World otter, Common otter
The Eurasian otter (Lutra lutra) is a semiaquatic mammal native to Eurasia. It is the most widely distributed member of the otter subfamily (Lutrinae) of the weasel family (Mustelidae). It is found in the waterways and coasts of Europe, many parts of Asia, and parts of northern Africa.
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NocturnalNocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal",...
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CrepuscularCrepuscular animals are those that are active primarily during twilight (that is, the periods of dawn and dusk). This is distinguished from diurnal...
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CarnivoreA carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
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PiscivoresA piscivore is a carnivorous animal that eats primarily fish. Piscivorous is equivalent to the Greek-derived word ichthyophagous. Fish were the die...
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SemiaquaticSemiaquatic animals are those that are primarily or partly terrestrial but that spend a large amount of time swimming or otherwise occupied in wate...
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AltricialAltricial animals are those species whose newly hatched or born young are relatively immobile. They lack hair or down, are not able to obtain food ...
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ViviparousAmong animals, viviparity is the development of the embryo inside the body of the parent. The term 'viviparity' and its adjective form 'viviparous'...
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BurrowingA burrow is a hole or tunnel excavated into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct ...
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TerritorialA territory is a sociographical area that which an animal consistently defends against the conspecific competition (or, occasionally, against anima...
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PredatorPredators are animals that kill and eat other organisms, their prey. Predators may actively search for or pursue prey or wait for it, often conceal...
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SolitaryNo
Not a migrantAnimals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
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starts withEurasian otters are brown above and cream below. These long, slender creatures are well-equipped for their aquatic habits. Their bones show osteosclerosis, increasing their density to reduce buoyancy. These otters differ from the North American river otter by their shorter necks, broader visage, greater space between the ears, and longer tails. However, Eurasian otters are the only otter in much of their range, so they are rarely confused for any other animal.
European otters live throughout Europe, North Africa, and Asia, inhabiting streams, rivers, lakes, freshwater and peat swamp forests, ocean shores, rice fields, fjords, caves, and other terrestrial habitats close by waterways. Dry resting sites and covered dens are found in tree roots, earth tunnels, boulder piles, banks, and shrubs.
European otters have their most active time at dusk and at night. During the day they are in their dens on the land, staying cool, and coming out at night to eat. They will spend several hours nightly foraging in water. They nest on the ground, tending to build underground tunnels to move between the two. They are solitary animals unless in a mating pair or mothers with their young. However, sometimes they form loosely knit groups numbering as many as 6 animals. They are the most territorial of otter species. Their territory can be as big as 40 km (25 miles) wide but is usually about 11 miles. They are able to cross territorial boundaries without incident, but aggressive behavior will occur if the same gender tries to enter a territory.
European otters are carnivores (piscivores). They eat mainly fish, but they also hunt amphibians and other aquatic prey, as well as birds, eggs, insects, worms, and a small amount of vegetation.
Although the mating system in European otters has not been well studied, they are thought to be either polygynous (one male mate with multiple females) or polygynandrous (promiscuous) (both males and females have multiple mates), as both males and females associate with each other only during mating. They will breed at any time during the year, most likely determined by the individual’s physiological state and reproductive maturity. Gestation is for 60 to 70 days, each female bearing 2 or 3 pups. The pups are 99 to 122gm when born, their eyes open at one month and after two months they leave the nest. Weaning takes place when they are 3 months old. They remain with their mothers up to the age of 14 months, reaching reproductive maturity at the age of 2 or 3 years.
The aquatic habitat of otters is very vulnerable in the face of change. Removal of vegetation from stream or river banks, the draining of wetlands, the construction of dams, and other man-made interventions greatly impact otter populations. Those living on the coast are susceptible to oil spills. The pollution of lakes and rivers affects the fish, their main food source. Other threats are being caught in nets and fishing traps set for other species, as well as being hunted for their coat.
The European otter has a wide distribution but no overall population estimate is available. According to scientific resources, the total population size of European otters in Belarus is around 12, 000 individuals, and in Sweden - 500-1000 individuals. According to the IUCN Red List, the overall estimate of the population in the United Kingdom was around 10,395 individuals in 2004. Currently, this species is classified as Near Threatened (NT), and its numbers today are decreasing.
