Eurasian otter

The Eurasian otter (Lutra lutra), also known as the European otter, is a semiaquatic mammal that lives in places like Eurasia and the Maghreb. It belongs to the otter subfamily of the weasel family and is found in rivers and coastal areas across Europe, much of Asia, and parts of North Africa. These animals are known for swimming well and are very good at catching fish.

Eurasian otters are mostly solitary and protect their own special areas, which they mark to keep other otters away. Even though they face danger in some places, their numbers are growing better in other areas thanks to efforts to help them. These clever animals are an important part of healthy water ecosystems.

Description

The Eurasian otter is a typical member of the otter family. It has brown fur on its back and cream-colored fur on its belly. These animals are long and slender, perfect for life in the water. Their bones are special, which helps them stay underwater longer.

This otter is different from the North American river otter because it has a shorter neck, a broader face, more space between its ears, and a longer tail. Usually, it measures between 57 to 95 cm (22.5 to 37.5 in) long, not counting its tail, which is 35–45 cm (14–17.5 in). Females are smaller than males. Most weigh between 7 to 12 kg (15 to 26 lb), but very large males can weigh up to 17 kg (37 lb). There are reports of one very big otter that may have weighed over 24 kg (53 lb), but this has not been confirmed.

Distribution and habitat

The Eurasian otter lives in many places, including Europe, parts of North Africa, and Asia as far as the Palestine region. Though it is no longer found in Liechtenstein and Switzerland, it is common in Latvia, along the coast of Norway, in western Spain and Portugal, and across Great Britain and Ireland. In Italy, it lives in the southern part of the country.

This otter prefers clean freshwater places like lakes, streams, rivers, canals, and ponds where it can find enough food. In Andalusia, it even uses artificial lakes on golf courses. It also lives along coastlines in saltwater but needs regular access to freshwater to keep its fur clean. In Syria, it has been seen in creeks and the lower Euphrates valley. In Nepal, it lives in rivers at high elevations, and in India, it is found in the Himalayan foothills, southern Western Ghats, and central India.

Behaviour and ecology

The Eurasian otter mainly eats fish, especially in places where fish are plentiful, like in the Mediterranean and cooler freshwater areas.

In winter or colder places, otters also eat amphibians, worms, clams, crustaceans, insects, eggs, birds, and small mammals, including young European beavers. They sometimes hunt larger animals, like adult greylag geese.

Eurasian otters live alone and mark their territory with their faeces, called spraints. These territories can be between 1 and 40 kilometres long, depending on food and hunting space. Males and females can have overlapping territories, but they only defend them against others of the same sex. Mating happens in water, and females can breed any time of the year. After a pregnancy of about 60 to 64 days, one to four pups are born. The pups stay with their mother for about 13 months, while the male does not help with caring for the young.

Taxonomy

The Eurasian otter used to be thought to include an extinct type called the Japanese otter as one of its subspecies. But newer research shows that the Japanese otter is actually its own special kind of animal, not just a variation of the Eurasian otter. Scientists are still not completely sure about all the details.

Conservation

The Eurasian otter faced big problems in the second half of the 20th century. Pollution from harmful chemicals and loss of places where they live were major issues. But now, things are getting better in many parts of Europe. For example, in the United Kingdom, otters are coming back strongly. This is thanks to bans on harmful chemicals, cleaner water, and laws that protect otters.

In places like Germany, Hong Kong, Bangladesh, Myanmar, Thailand, and Mongolia, otters still need a lot of help to stay safe. Special groups work to protect their homes and help them grow in number. Scientists have studied the otters' genes and found that even with fewer numbers, they still have good genetic health. However, changes in their food supply, like fewer native fish and more foreign species, could still be a challenge for their future.