In search of wildlife on a one-day cruise off the coast of Cornwall, UK

London: It’s called the ‘sunlight zone’ — paradoxically, I feel, because as I look over the boat’s side into the steely-blue water lapping against the hull, all I see is a dark, mysterious mass. This uppermost realm of the ocean is more formally known as the ‘epipelagic’, where the sun is able to penetrate and spark life into a menagerie of marine flora and fauna — like the seagrass visible on my port side, or the little fish and molluscs scooped up by the black-feathered shags gliding to starboard. The ‘twilight zone’ is what lies beneath that — a shadowy realm of ocean giants like whales, sharks and colossal squid. Venture even deeper for the midnight and abyssal zones, about which scientists know very little. Their ominous blackness conceal organisms you could swear were interplanetary. But Captain Keith won’t be taking us there — thank goodness — as much as visiting Cornwall’s remote west feels as though you’ve reached the ends of the earth.

Today, Cornwall’s legendary sea captain is taking us on a voyage from Falmouth Bay to the craggy coastline of the Lizard Peninsula aboard catamaran The Spirit of the Seas. As I settle into my seat, I hear a gaggle of twitchers chatter about the sea birds we’re likely to spot — skuas, phalaropes, razorbills and others — while a wide-eyed couple at the front of the boat anxiously swallow the sea sickness tablets they forgot to take two hours ago. Beth, a young Bristolian woman sitting next to me, admits she’s not so interested in the avian sightings, what she’s really looking forward to is the chance to spot a humpback whale.

“Whales are being spotted in Cornish waters more and more in recent years,” Captain Keith declares in his pre-departure brief, puffing out his chest with pride, “including the odd humpback — but that’s rare.” Beth blinks away her disappointment. “I’ve spotted over 40 gorgeous minke and fin whales this year alone, though, so keep your eyes peeled.”

The greater number of whales is a sure sign of recovery, we’re told. Careful management of shipping and fishing practices in this coastal county has thrown a lifeline to these threatened megafauna, as well as other marine life. And tangibly so, because as soon as we’re away from the estuary, we’re catapulted into a ‘work-up’ — that’s captain talk for a hunting expedition that explodes to the surface. We’re surrounded on all sides by torpedo-like Atlantic bluefin tuna launching their strong, silver bodies into the air — the crescent shape of their tail fins unmistakable. Having been fished to near oblivion until the 1960s, tuna fishing has been strictly regulated in the UK ever since, the frenzy we’re witnessing is a sign of better times for the 1,500lb beasts.

We continue on to The Manacles, heaven for perching birds, hell for passing ships. These fangs of razor-sharp rock protruding from the reef below us sank the HMS Primrose in 1809 — with just one of the 126 crew surviving — and many other vessels besides. Today, it’s where coastal birds rest their wings and daredevil divers brave the depths to explore a cemetery of mangled shipwrecks.

“Purple sandpiper!” somebody shouts, initiating a rush of binocular-wielding birders to port side that prompts Captain Keith to reach for the intercom. “Could we try to keep roughly six people on either side of the boat to distribute the weight,” he interjects. “Seal at the bow everybody! Atlantic grey seals at the bow!”

A little while later, the sun lowers on the horizon as we head back to Falmouth Bay, the sunlight zone beneath taking on an ethereal new form. Sitting at the bow, I’m mesmerised by the shades of honey shimmering amid the blue, the sea’s drifting minerals glittering up at me like gold dust. As I close my eyes to soak in autumn’s ever-waning warmth, I hear a tearing rip of water beneath — something is travelling at speed, and it’s directly in front of us. I scan the sea for life and a necklace of bubbles rises and pops at the surface. Soon after, a dolphin’s smooth, blue-grey body leaps from the water. She’s guiding us home. Her calf appears at her side, the stripes of its foetal folds still visible by the dorsal fin. As the pod swells to four, five, six, I remember my duty to inform the others of the sighting and selfishly consider whether I’d prefer to enjoy it alone.

Orca and minke whales, sea and golden eagles, basking sharks and many sea bird species are just some of the wildlife-spotting opportunities afforded by the guided Mull Odyssey Cruise around Scotland’s Isle of Mull, departing in April 2024 from Oban. En route you’ll visit Fingal’s Cave, a geological wonder, as well as Iona, sometimes dubbed the birthplace of Western Christianity. Six nights from £1,960 per person.

Departing from Marloes in Wales, this company offers whistle-stop tours of Pembrokeshire’s wildlife-rich islands, including Skomer, famed for its bright-beaked puffins; Skokholm, whose skies are often filled with storm petrels and Manx shearwaters; and Grassholm, whose colony of gannets always bring the drama as they spear the water in search of food. Day tour £60 per person.

Reams of legend envelop Ireland’s storied coastline, where lush green landscapes meet foreboding black sea cliffs and the mists of the Atlantic Ocean. Discover it all — from the Cliffs of Moher to the Giant’s Causeway, with a little of Scotland’s Inner Hebrides thrown in for good measure — on this cruise, departing in August 2024 from Liverpool. Eight nights from £1,299 per person.

Departing in May 2024 from Southampton, the Discovering Normandy & the Channel Islands cruise first stops at St Mary’s, one of the Isles of Scilly, where birdwatching opportunities abound, before continuing on to Guernsey, where you’ll explore the coastal idylls of St Peter Port, Brecqhou, Sark and Alderney. Honfleur, an island in Normandy steeped in medieval history, is the final stop. Five nights from £873 per person.