Porpoise everywhere at first light. Porpoise to the bow and stern. Porpoise off the coast of Raasay and the whaleback Crowlin islands. Porpoise hidden from passengers driving over the Skye bridge, but clearly visible from the shelter deck of our vessel as we slide out north towards Loch Torridon. Before long, a pod surrounds the boat, sickle fins glinting white in the winter sun. A little way ahead, near the shores of Applecross, two cormorants dance across the ice-cold sea.

The cormorants are appropriate. I’m on board the hardy Nova Spero, a teal-blue, low-impact vessel operated by new adventure cruise operator Skarv Lines – skarv being Gaelic and Old Norse for these black seabirds. But unlike cormorants, which are known for their guttural grunts, the eco-friendly boat can operate almost silently, powered by a battery to reduce carbon emissions and noise pollution on sea lochs and canals.

Launched in summer 2020, the Nova Spero’s trips explore the rawest stretches of the Highlands’ Atlantic and North Sea coastlines. Bolder still, the boat does so in winter. Sailings are also in the pipeline to Newcastle, Northumberland and Norway, but today we are mapping an untested route from Corpach near Fort William, through the Inner Hebrides via Mull, to Torridon and Raasay. Already, we’ve seen dolphin, porpoise and seals, as well as crisp snowfall on the tops of Ben Nevis and Càrn Mòr Dearg. It is hauntingly beautiful.

But this is not a cruise in any traditional sense of the word. The boat, now a converted sightseeing vessel for sardine-snug passengers, was originally a wooden-hulled fishing trawler that scoured for tuna from Newlyn in Cornwall to the Bay of Biscay. The seven heated cabins, sleeping 14 guests, are in the hold, where 50-odd tonnes of fish were once stored on ice. True to the vessel’s origin, the storm hatches, shipping bell and landing winch remain, as do the searchlight and the blackened towing gantry for the trawling net. Guests are given oilskins for bad weather and invited to help out on deck or just hold tight and savour the snowball-fresh sea air. Best of all, moorings can be tailored to guests’ wishes, creating a bespoke adventure of sea kayaking, hiking, birdwatching or distillery touring.

A Gaelic proverb is apt on the first day’s sailing, from Corpach to Tobermory: Am fear a bhios fad aig an aiseig gheibh e thairis uaireigin. Which means, “He that waits long for the ferry will get across sometime.”

Every so often we round a knobbly point of land, hoping to see a swooping bird of prey or dorsal fin in the sea channels. Soon, near the cool reaches of Loch Aline, we are transfixed by blubbery cetaceans, white-tailed eagles and glorious snow-fuzzed summits. There’s no sign of the yachts and other vessels that arrive in summer, just views of lonely chess-piece lighthouses and dazzling empty beaches.

When it comes to finding the most untouched spots, it helps that the crew are so connected to the sea. The boat’s owner, John MacInnes, is a master mariner from Eriskay; one of his recent jobs was to transport colossal anchor handlers from Aberdeen to oil rigs down the coast of Brazil. In the sunken wheelhouse is skipper Bill Summers, a scallop fisher from Skye who retired but found that he missed the sea too much.

“If you can take the unpredictable winter weather, you can see some truly stunning places,” says John, while we navigate a choppy swell around Ardnamurchan lighthouse, one of the British mainland’s most westerly points. “Plus, at this time of year, we have the Highland coast completely to ourselves. Well … almost.”

As if to mark his words, we pass through a favourite stomping ground of a west coast community of killer whales, but see only ripples. The abundant marine life – orcas, minke whale, short-beaked common dolphin, Risso’s dolphin, harbour porpoise – is the same year-round, but the cooler weather and shifting winds mean that the seas are eerily quiet and the only traffic is working scallop and langoustine boats.

Which is why the fisherman’s code helps. Local people recognise the trawler’s telltale signs – on this trip, the Saint Piran’s flag and the blue and pea-green cross of South Uist – and at the quayside, hard-earned shellfish catches are brought on for a discount price. When we are moored at Kyle of Lochalsh on the second night, dinner in front of the woodburner is hot-smoked salmon and hand-dived queen scallops from Sconser on Skye. Whisky, bought earlier at the Tobermory distillery, follows on deck, beneath a sky glowing with stars.

The next morning, we push out past salmon farms and fishing grounds into a calm sea, rolling towards Skye, just as Bonnie Prince Charlie did when he fled for his life in 1746. Along this coast, the ghosts of history are always present. One particularly tragic story tells of the loss of 201 Lewis men who perished when HMY Iolaire struck the notorious Beasts of Holm rocks off Stornoway at 2am on New Year’s Day 1919. Poignantly, they were returning home at the end of the first world war. A plaque honouring them marks the entrance to the Kyle Line railway museum.

Later that afternoon, we sail down sky-mirrored Loch Torridon, where there is such clarity of tilting light on water that it feels as if we are crossing through the looking-glass into a new realm. Snow fluffs the summits of Beinn Alligin and Beinn Eighe, and we take Nova Spero’s rib (rigid inflatable boat) for a magical shore ride to Torridon village. It is silent and empty, making the mountains all the more intimate.

Our final destination is Raasay, a highlight for Samuel Johnson and James Boswell on their 1773 Hebridean tour. Nowadays it boasts a landmark, if incongruously stylish, whisky and gin distillery. The island’s shores plunge into the deepest seas in Britain, and we spy rutting red deer ranging over its northern moors. Spectacular sea-to-summit views of Skye as we journey back south are a given.

The ragged Hebridean coast may not be quite as far away and inaccessible as it once was, but it still feels like a long way from home – and has a particular, lonely charm in winter. That is its appeal: the fantastical marine creatures, the unheard-of sea lochs, the Narnia peaks. We drink it all in. And as for Nova Spero? It means “new hope”. Which in times like these is something we all need more than ever.
The trip was provided by Skarv Lines, which offers year-round, multi-day cruises. The four-night winter Loch Linnhe, Oban & Mull cruise costs from £880 pp all-inclusive

Three more UK winter adventures

Somerset

The One Show’s Mike Dilger leads a four-day trip centred on the Avalon Marshes in the Somerset Levels, winter home of thousands of waterfowl, plus birds of prey and otters. Highlights may include enormous murmurations of starlings and a flock of rare cranes.
£625pp half-board, next trip 9 January 2022, wildlifeworldwide.com

Norfolk

The wetlands, woods and dunes of north Norfolk are perfect for a long weekend of birdwatching. As well as geese, ducks and waders, there is a chance to see seasonal visitors such as rough-legged buzzards, snow bunting, shore larks and waxwings. One evening is spent in search of owls.
£395pp half-board, next trip 10 December, naturetrek.co.uk

Cairngorms and central Highlands

This five-day tour takes in habitats from rivers and lagoons to pine forests and mountains to maximise wildlife encounters. Fingers crossed for red deer, red squirrels, pine martens, mountain hares, capercaillies, snow bunting and ptarmigan.
£795 with accommodation and most meals, next trip 24 February 2022, wildernessscotland.com