How to recognise an otter
The European otter is a sleek, brown semi-aquatic mammal, typically 60–80 cm long with a thick tapering tail that makes up roughly a third of its body. Up close, the pale cream throat and chin are distinctive — but most sightings are brief glimpses of a brown shape slipping into water.
In water, look for a V-shaped ripple moving without a visible wake, a smooth arching dive, or just a ring of ripples where something slipped under. On land, the gait is a low bounding lope; the body appears long and low to the ground.
Otter tracks show five toes with a distinctive webbing impression and a large, rounded pad. They are often found in mud near the water's edge. Spraint — the otter's dropping — is left conspicuously on rocks and tree roots as territory marking and has a pungent, grassy or fishy smell quite unlike fox or mink scat.
Where otters live in the South West
Otters need clean, unpolluted water with a reliable fish supply and enough bankside vegetation to provide cover and holts — the dens where they rest and raise cubs. Dartmoor's granite river systems and the wooded valleys of Exmoor provide exactly this, and both have seen population recoveries since the 1970s.
They are territorial and wide-ranging, with a dog otter covering 20–40 km of river in a night's travel. This means that even in good otter country, spotting one is never guaranteed at any particular location. Coastal otters do exist, particularly in west Cornwall, where they hunt in tidal pools, but most South West otters are freshwater river animals.
The Dart, Exe, Teign, Barle and Camel are all known to hold otters. Quieter tributaries and smaller moorland streams are often used for breeding and resting.
Signs of otters — what to look for
Signs are far more reliably found than otters themselves. A methodical approach along a riverbank will often reveal evidence even where you won't see the animal.
Spraint
Dark, tarry droppings on exposed rocks, roots or sandy banks. Often has a distinctive musky, fishy smell. Placed prominently as territorial markers.
Fish remains
Otter will eat fish starting from the head and working down, sometimes leaving the tail end. Often found near favoured feeding rocks.
Footprints
Five-toed prints with webbing marks in soft mud near the water's edge. Roughly 6–7 cm wide. Look at sand bars and muddy margins after rain.
Slide marks
Smooth chutes in mud or snow on steep banks — especially common in winter when otters slide into water. Not always present.
When you might see one
Otters are primarily nocturnal, but activity patterns vary by location and season. In areas with low disturbance — remote moorland streams, quiet tidal creeks — they are more likely to be active in daylight, particularly at dawn and in the hour before dusk.
Winter can be productive: reduced vegetation means better sightlines, and otters need to feed more actively in cold conditions. After floods, they often move to slower water and can be seen hunting in more open areas. Summer activity tends to be compressed into the darker parts of the day.
Otters are active year-round — they do not hibernate. Cubs are typically born in spring but can appear at almost any time, and a female with cubs at heel is one of the more remarkable wildlife encounters the South West offers.
How to watch responsibly
Otters are protected under the Wildlife and Countryside Act 1981. It is illegal to intentionally disturb them at or near their holts. If you encounter an otter, stay still, stay quiet, and do not follow it if it moves away.
Specific holt locations are not published and should not be shared publicly. Even well-intentioned attention creates disturbance. Keep dogs on leads near known otter rivers, especially in spring when cubs may be present.
The best sightings come to people who move quietly, wait patiently and treat the river as shared space. If you disturb an otter, it won't return — so restraint benefits the next visitor too.
Why otters matter
Otters are apex predators of freshwater systems. Their presence indicates clean water, healthy fish populations and functioning wetland habitat. In the mid-twentieth century, pesticide pollution and habitat destruction drove otters close to extinction across much of Britain. The South West retained small populations through this period.
The recovery since the 1980s is one of British conservation's clearer success stories — the result of pesticide bans, cleaner river management and legal protection. Seeing an otter today is a measure of that improvement.
Supporting river quality, avoiding bankside disturbance during sensitive months, and reporting sightings to the Environment Agency all contribute to their continued recovery.