Otters are Back! The Return of Britain’s Mesmerising Mustelids

Exceptional hunters, sensational swimmers and sleek in the water, otters are one of Britain’s most charming native animals. Dr. Orton investigates how otters went from the brink of extinction to becoming one of Britain’s conservation success stories.

This is part of our rewilding series, a comprehensive guide to some of Britain’s rarest species with links to academic literature. For a quicker, more accessible read, you can read our posts about the nocturnal animals that live in our woods or our baby tawny owls!

About Otters

Otters are one of our native British mustelids (from the mustelidae family, along with badgers, weasels, stoats, pole cats, pine martins and ferrets). Common otters are also known as European otters, Eurasian otters and also by their Latin name, lutra lutra.

They live in rivers, canals, lakes, wetlands and along coastlines (as long as there is a freshwater supply nearby). In Scotland, a perhaps half of the otters are coastal, an unusually high proportion.

In the UK, coastal otters are sometimes called “sea otters,” but these are different from the true sea otters (enhydra lutris) that live in the North pacific. The UK’s coastal otters are also Eurasian otters, but usually have a much smaller home range than the river otters because of the higher density of prey in the oceans. These otters still need a source of fresh water for drinking and to rinse the salt from their fur so it retains its insulating properties.

Otters are excellent swimmers and have long, sleek bodies with long muscular tails and webbed feet. Otters are carnivores, eating fish like trout, carp and eels, amphibians and crustaceans. Their sensitive whiskers and claws help them to detect and catch their prey – sometimes the otter’s prey is equal to its own body weight! On land, they will hunt birds like moorhens and coots, eggs, insects and even small mammals.

Otters are mostly solitary, but come together to breed, which can happen year-round. Baby otters are known as cubs or pups and are usually born in pairs or triplets between May and August. The cubs are raised by their mother until they are around a year old.

Otter nests are known as holts, some of which have more than one chamber and a latrine connected by tunnels. They have multiple entrances, some of which might be underwater. Otter holts are found in riverbanks, tree roots, or rocky crevices and the otters will line them with natural material such as grasses. 

Otters in Britain

Otters are historic residents of the UK and play an important role in our folklore. One of my favourite English saints had a very special relationship with otters: the otters used to dry the feet of St. Cuthbert when he went into the sea to pray!

Welsh folk goddess Ceridwen was said to have turned into an otter in pursuit of a young boy who had obtained the wisdom she had intended for her son. In the Irish nautical folktale, The Voyage of Maelduin, a holy man tells the story of how otters brought him salmon and firewood, allowing him to live for seven years. In Scotland, there are stories of dratsie (otter) kings, wish granting creatures accompanied by seven black otters.

Otters are also popular in classic literature, such as the character Otter in Kenneth Grahame’s The Wind in the Willows, Henry Williamson’s Tarka the Otter and Gavin Maxwell’s Ring of Bright Water.

Otter specialist D. J. Jefferies points out that, in the 18th and 19th centuries, otters were persecuted for fishery protection and sport and declined further in the 1920s and 1930s due to otter hunting with packs of hounds.

By the 1950s, the little mustelids were on the brink of extinction. This was partly due to hunting and habitat destruction, but the use of synthetic pesticides in British agriculture following World War II was also a major factor.

Environmentalist writer Rachel Carson warned in her 1962 classic Silent Spring that the indiscriminate use of pesticides such as dichlorodiphenyltrichloroethane (DDT) causes severe harm to humans and animals throughout the food chain.

In the UK, DDT was banned in 1984, but the ecological legacy of DDT is that it continues to damage ecosystems 50 years after it was last used. Today, glyphosate is common in many herbicides and is toxic towards plants and animals.

Otters are Back!

The good news is that the UK’s rivers have returned to better health thanks to various clean-up efforts. In Leicestershire, organisations like UOCEAN run river clean-ups and other activities.

Otters and their dens were protected by the Wildlife and Countryside Act in 1981 and by 2011, otters had returned to every county in Britain. The Woodland Trust helps otters by maintaining artificial holts and allowing scrubby thickets to grow along river banks in their woods.

This is good news for our wildlife in general. Rewilding Britain point out that otters’ presence in a freshwater habitat alters prey (fish) behaviour and keeps fish population sizes in check. A team from Oxford University found that otters might help to control American mink, an invasive species that has devastated our native water voles. European otters are around seven times larger than American mink and their presence is associated with the mink’s diets becoming more terrestrial.

Some commercial fishery owners are concerned about losing fish to otters, but  groups like the UK Wild Otter Trust, and the Angling Trust have been in dialogue with fishery owners to find a solution. As a result, Natural England do occasionally issue licences to allow trapping and removal of otters from within a fenced fishery.

Otters have returned to Leicester due to cleaner rivers and in Leicestershire more generally along the Rivers Biam and Soar.

How to Spot an Otter

Otters are difficult to spot, but you might try looking in scrub, woodland, marsh and waterway islands. Try looking for otters at dawn and dusk.

Our otters are mostly solitary, but come together during the mating season and stay together in groups of up to six for a short time after their pups are born. Otter territories might be one to twenty five miles, but otters will stick to and defend these territories.

You might start by looking for otter tracks on water banks. The tracks will be 4-8cm wide, with usually four out of their five toes showing. You might see the webbing between toes, although you usually won’t see their claw marks. You also might find slipways made by otters sliding on their fronts. Look for holts in large, established trees along water edges, particularly ash and sycamore trees.

You could also look out for the otters’ spraint (droppings) on rocks and logs and under bridges close to the water. These are green-black-grey with a sweet, musky smell and contain bones, shells, feathers and fur. Otters leave them to communicate with other otters. 

Look around reedbeds too, where otters often hunt. If you see a stream of bubbles in the water, this could be evidence of a diving otter; a V-shaped wake follows a swimming otter. Other animals might also give you a clue: ducks suddenly swimming away, glancing over their shoulders, could be a sign of an otter on the hunt.

In our next post, read about the water vole: our countryside emblem!

Find Out More

If you’re interested in conservation and wildlife, we have a blog series on British wildlife and a series on the people and wildlife of South Asia, from the altitudes of the Himalayas to the dense mangrove forests of Bangladesh! You might be interested in Dr. Orton’s blog post about the traditional art of fishing with smooth-coated otters (lutrogale perspicillata) in Bangladesh!

We also offer online private tuition in our interdisciplinary course, Culture and Conservation, in which you can explore the links between our natural and cultural heritage and study wildlife and cultures from across the world! This is a template of a possible study route and can be combined, adapted, or designed from scratch to suit your interests and goals.

Dr. Orton will work with you to design a course of private tutorials tailored to your needs, ability and schedule. Click the link to find out what it’s like to work with her and contact us to find out more!

Do More

For those who would like to take action to preserve our wild spaces, there’s plenty you can do. If you're lucky enough to have some land, you could plant a wood from scratch (click the link to read about how we are planting our own native woodland). Even if you don’t have a big garden, there are plenty of things you can do to help biodiversity in your area. Why not put up a solitary bee nesting box or insect home, create a woodpile as a habitat for small creatures or leave small areas of your garden to go wild?

If you live in the Leicestershire area, contact UOCEAN for information on river clean-ups. 

Think about your own area and how you can protect vulnerable but important parts of your own environment. You might even want to start your own project investigating the cultural importance of wildlife in your area. Dr. Orton works with independent scholars undertaking their own research for an independent project, people writing a book or simply those who have a personal interest. Click the link to find out what it’s like to work with her and contact us to get started!

Reach Out

We’d love to see what you’re doing to help wildlife in your area. Follow the Conservation highlight reel on the Orton Academy Instagram to see what we’re getting up to and tag us in to any snaps you put up!