Journey to the source: Monty Halls' marine adventures

I'm standing in one of the planet's most challenging landscapes. Forget the deserts of Africa and the wastes of the Antarctic; my location is a sandy cove near Dartmouth in South Devon. "Only the physiologically elite survives on the seashore," says my guide, Monty Halls.

And Monty should know. He served for many years as a Royal Marine and he's a qualified marine biologist. He's already drawn on his spirit of derring-do and his fascination with coastal life to become a familiar face through his TV series Monty Halls' Great Escape and The Fisherman's Apprentice. Now he's harnessed his redoubtable skills for another project, Monty Halls Great Escapes, a tour company offering trips on and off the local coast, which he and his assistant Rachel, also a marine biologist, lead from the shop he opened this spring in Dartmouth.

I'm sampling one of those trips, "The Ultimate Taste of Devon", a half-day exploration featuring wildlife-spotting out at sea in a fast boat (though my voyage is scuppered by 30-knot winds), a guided shore walk and a hike along the coast path, efforts rewarded by a picnic plucked from and produced in the surrounding landscape. Monty's idea is to celebrate the local environment, by exploring the area and then enjoying what's produced in it, conducting marine research and supporting local businesses as he goes.

Back on the beach, the science is coming thick and fast. Monty is explaining about "zonation", how "the stuff at the top of the beach is more orientated towards the land system and the stuff at the waterline is more orientated towards the marine system". However, he's keen to keep the lectures short and make the experience interactive. So, we soon set about searching for some of the inhabitants of this rocky laboratory.

Ten minutes later, Monty picks through our aquatic treasure trove and holds up a limpet. "The way limpets distribute across the beach – you get the young crazy males in the surf with their shirts off, and at the top end of the sands you get the little old ladies reading Agatha Christie novels. One of the problems all the animals have down here is drying out – they can desiccate. The limpet makes a homing scar on the rock that it sits in. It's water tight, so when the sea goes out it remains nice and moist."

Next, we inspect a dog whelk. Monty tells me that they prey on mussels, which get their own back by trapping the invader Gulliver-like with their byssal threads. (That's the beard to you and me.) And I learn about how the barnacle spends its life on its back, gathering food with its feet. "The barnacle has got the largest willy of any animal," says Monty. "Because it's stuck, the willy goes calling. It's the proportional equivalent of a human being having one the size of Nelson's Column."

Monty modestly advises me to double-check his facts. But his entertaining commentary is half the fun, and enlightened by this light-touch foray into the scientific world, I head for lunch. It's less a picnic, more a feast, the provenance of which has been carefully noted. There's smoked chicken from Mike's Smokehouse in Loddiswell, Devon blue cheese from Ticklemore Cheese in Totnes, and ploughman's pickle from the Kitchen Garden at Strete.

But my favourite is the crab, bought fresh at Brixham fish market that morning. Monty is passionate about supporting Britain's inshore fishermen, whom he admires for their ill-rewarded hard work. There are just 6,000 operating around our coast, he tells me, a third fewer than half a century ago. It's an issue he addressed in The Fisherman's Apprentice and I sense a campaign in the offing.

Monty is not alone in championing the local catch. That evening, I take up his recommendation to sample some of it at the Seahorse, a restaurant just around the corner from Monty's base, run by chef Mitch Tonks. Mitch is off for the night, but the quality of food, an Italian spin on the morning's landings, speaks for itself. Squid from the bay is grilled over fire with peppers, oregano and chilli. Locally caught monkfish, John Dory, red gurnard, gambero rosso, soft shell crab and whitebait create a spectacular fritto misto di mare. And Dartmouth lobster is roasted and embellished with just garlic. The simplicity is as deceptive as it is refreshing, focusing on the food rather than fancy presentation.

The next morning, I venture out for a shore walk of my own. My lodgings, At the Beach, a complex of 13 smart apartments in a former Victorian hotel, just along the coast from Dartmouth at Torcross, are ideally situated for such exploration. This strip of shingle at the southern edge of Slapton Sands, separated by a slither of road from the freshwater lake of Slapton Ley, should make for an interesting hunting ground.

I root around for inspiration, though I'm a little thrown. This open expanse seems quite different from the sheltered cove I explored with Monty, and it's not quite the same without his ebullient presence.

I'll just have to brush up on my marine biology by booking another tour.

Travel Essentials

Getting there

Kate Simon travelled to South Devon courtesy of First Great Western (08457 000 125; firstgreatwestern.co.uk). Totnes is the nearest station to Dartmouth and Torcross on the London-Penzance mainline. London Paddington to Totnes costs from £12.50 each way. First Group (0845 600 1420; firstgroup.com) runs bus services between Totnes, Dartmouth and Torcross.

Staying there

Blue Chip Holidays (0844 2730 983; bluechipholidays.co.uk) offers three nights At the Beach (bch.so/at-the-beach) in an apartment sleeping six from £283.

Eating there

Monty Halls Great Escapes (01803 431858; montyhalls.co.uk) offers "The Ultimate Taste of Devon" for £50 per person. Other activities and courses are also available. The Seahorse (01803 835147; seahorserestaurant.co.uk) is open from Tuesday dinner through to Sunday lunchtime and offers two-course lunches from £20 per head, and a three-course dinner from £27, without drinks.