Why Britain's Otters Are Closer Than You Think

Mention otters to most people and they picture remote Highland lochs or windswept Cornish coves. The truth is more encouraging. After decades of decline, the Eurasian otter has clawed its way back across much of England, Wales and Scotland, and healthy populations now live within a few miles of towns, cities and busy commuter villages. They follow the fish, and where there are rivers with reasonable water quality, plenty of bankside cover and a decent supply of coarse fish, you have a fair chance of otters — even if you never actually lay eyes on one.

That last point matters. Seeing an otter is a privilege, not a guarantee. But you can enjoy them every time you walk a riverbank, because otters leave a trail of evidence behind them. Learning to read that trail turns an ordinary stroll into something closer to detective work, and it is the single best way to improve your chances of a sighting.

Reading the Signs: Spraints, Prints and Slides

The classic otter calling card is the spraint. This is the animal's droppings, and otters deliberately leave them in prominent places — a flat boulder mid-river, a grassy tussock on a bend, the top of a fallen trunk, the apron beneath a bridge. Fresh spraint is black or dark brown, tarry, and usually full of fish bones and scales. It smells surprisingly sweet and fishy, rather like a mixture of jasmine tea and a fishmonger's back step, and it can be detected from a couple of metres away when it is fresh.

Sprants are scent messages. Otters use them to advertise territories and to keep in touch with neighbours. Once you find one, look around — you will often find a whole series of them spaced along a stretch of bank.

Other signs to look for include:

• Prints in soft mud or silt along the water's edge. Otter prints show five toes, often with a faint webbing mark, and an infrequent, broad pad shape. They are much bigger than most people expect — typically around 6 to 9cm across — and the walking pattern tends to be a loose, loping trail rather than a neat line.
• Slides where otters have belly-flopped down a muddy or snowy bank into the water. These look like smooth, polished chutes with a fan of scattered mud at the bottom.
• Feeding remains — half-eaten fish, neatly peeled crayfish shells, or a pile of bones left on a flat stone or a protruding root.
• Anal jelly, a firm, translucent, amber-coloured deposit that looks a little like a blob of marmalade. It is left on banks and stones and is a reliable indicator of a territory being actively used.
• Paths worn through vegetation along the water's edge, especially where the bank is steep and otters are moving from one pool to another.

If you are unsure whether you are looking at otter or mink signs, size is your guide. Mink prints are smaller, more circular and neater, and mink spraint is thinner and contains more fur and feather than bone.

Holts, Couches and Other Resting Places

Otters need somewhere dry and quiet to rest, and they use two kinds of place. A holt is an underground den, often dug into a riverbank among the roots of an alder, sycamore or willow, or sometimes in an old rabbit warren or beneath a stone bridge. A couch is an above-ground resting spot — a flattened patch in tall grass, reeds or under a tangle of brambles, often on a small island or a secluded bank.

You will rarely see these places directly, but you can spot the clues: worn runs leading into dense cover, a fresh spraint nearby, or a patch of flattened vegetation at the top of a bank. Once you have found a likely holt, treat the area with real care. Otters are shy, and a female with cubs will abandon a site if she feels harassed.

Timing Your Walk: Dawn, Weather and the Seasons

For most of the year, otters are crepuscular and nocturnal, doing the bulk of their hunting between dusk and the early hours. That makes dawn the single best time to be on the river. Arrive before first light, settle yourself somewhere with a clear view of a long pool or a bend, and let the river come to you. The half hour either side of sunrise is when otters are most likely to be finishing a night's fishing or moving between feeding areas.

Winter is often underrated. Vegetation dies back, so cover is thinner and views are longer, and otters are more active in daylight during the colder months. Cold, still mornings with a touch of mist are excellent. So is the hour after a spell of heavy rain has eased, when rivers are running coloured and fish are easier to catch — though you should never venture onto a swollen, fast-flowing river for safety reasons.

Summer is harder going. Look instead at dusk, particularly on overcast evenings, and concentrate on quiet stretches away from footpaths and dog walkers. In some urban rivers, otters have become surprisingly tolerant of people and daytime sightings are genuinely possible — Bristol, Birmingham and Sheffield all have their resident animals.

How to Watch Without Disturbing Them

Your first sighting is usually a V-shaped wake moving across a still pool, or a dark, low-slung body slipping off a bank with barely a splash. Otters surface briefly, often showing just a head, before diving again for twenty or thirty seconds. Listen for a sharp, high whistle — that is an otter contact call, and it is worth learning.

To give yourself the best chance without causing harm:

• Wear dull, natural colours and move slowly and quietly. Sit still — patience beats stalking every time.
• Keep well back from the water's edge, use a bank or a tree to break up your outline, and stop talking.
• Carry binoculars, ideally 8x42 or similar, which perform well in low light. A spotting scope is useful on wide, open stretches.
• Keep dogs on a short lead and out of the water, and never let them investigate a holt.
• Never approach a holt or a couch, and never use a torch on an otter at night. All otters are protected by law from disturbance, and repeated pressure can drive a family group away from a stretch of river entirely.
• Take photographs without flash, and if an otter stops feeding to stare at you, you are too close — back off quietly.

Getting Your Eye In on Your Local River

The most rewarding approach is to adopt a short stretch of river and walk it regularly. Pick somewhere with a mix of pools, riffles, overhanging trees and islands, and visit at different times over several weeks. Note where you find spraints, watch how the water levels change, and pay attention to what the local anglers and river keepers say — they usually know exactly which bends are being worked.

Keep a small notebook and record what you find and where. Within a season, you will start to see patterns: favourite spraint sites, regular crossing points, the pools an otter works on its way upstream. And then, one quiet morning, you will catch a ripple where there should not be one, and an otter will pause, look at you, and vanish. It is a moment worth every early start.