Monty Halls's exploration of North Uist reveals its harsh beauty and untapped potential

• Picture: TSPL

The Outer Hebrides may be isolated but you're never truly alone. In the city, of course, we all keep ourselves to ourselves and call that a community." Hearing Monty Halls wax lyrical about his home in North Uist for the best part of 2009, I'm reminded of my own sense of discovery arriving on a bike and a cloud of midges for another BBC series four years ago. The Southern Isles from Barra to Berneray are casually and jaw-droppingly splendid. And empty.

"I can't get over the untapped potential of these islands," he says. "If they were lying off Australia, there would be surf schools and diving centres, adventure programmes and climbing groups. Sollas beach is quite simply the best surf beach I've ever seen anywhere. The Western Isles are Britain's New Zealand. But these islands are dying. All the locals said one thing to me: make it a good show. They feel, they know this could be the Uist's big chance … or their last chance."

Monty Halls, 43, is a writer, explorer, television presenter and an impressive public speaker. A former Royal Marines officer who worked for Nelson Mandela on the peace process in South Africa, he left the services in 1996 to complete a marine biology degree and has since circumnavigated the globe four times. He has led an anti-poaching project in the grasslands of northern Malawi, an excavation off the coast of Tamil Nadu in India, and an expedition to photograph a rare crocodile species in Central America.

Halls's television career began when he won Channel 4's Superhuman competition in 2004, presenting documentaries for Discovery, National Geographic, the BBC and Channel 4. But his latest projects have taken place closer to home, on the west coast of Scotland, where he went "back to basics" living in a tiny bothy on the Applecross peninsula beach for six months in 2008, following in the footsteps of his hero, the naturalist Gavin Maxwell.

Monty Halls' Great Escape, gained viewing figures of three million, which was enough to justify a return trip. But unlike his solitary Applecross adventure, Monty Halls' Great Hebridean Escape is a double act. He describes local guide James (Jimmy) MacLetchie as his inspiration, saying: "Without his knowledge and overwhelming enthusiasm we would have struggled to make this series." Praise indeed for the Gaelic-speaking, naturalist, countryside ranger, guide, ghillie and singer. And long overdue recognition for well-honed skills that often seem like second nature. MacLetchie, 47, came to Uist from Glasgow at the age of six to foster parents Maggie and Archie Morrison. "My first memory was being shown a map of the Hebrides in a dark room in Glasgow. My first memory of being held was outside the croft house on North Uist. These islands are home."

MacLetchie's new parents were fluent Gaelic speakers. His mother, who died last week, was headmistress at the local primary school in Sollas and his dad a crofter who also worked in the seaweed factory at Lochmaddy. As he grew up, MacLetchie slowly realised he was living in a secret paradise, both protected and threatened by the ignorance of mainland Scots, two hours' ferry and several hours' car journey distant.

"I'm amused when I see Blue Flag beaches in the UK, knowing that the Uists and Barra have over 30 powder white beaches which take your breath away but have no classification because they are just as nature intended – without facilities," says MacLetchie. The wildlife on North Uist is outstanding, including 11 species of whale and dolphin, 20,000 grey seals, countless wading birds and rare habitats like the flower– encrusted machair land. The landmass contains 10 per cent of the UK's freshwater, which means a lot of lochans, swans and crannogs; there are 108 of the little loch-bound islets. Defensive or decorative – no-one quite knows.

The Udal peninsula was an early Viking settlement. The entire west coast is a long fine, white, sandy beach. Lochmaddy is the largest sea loch in Britain – its myriad fragments and coves offered shelter to Hebridean pirates, acted as makeshift lobster pens and lay beneath clouds of acrid smoke as crofters burnt kelp for a residue that helped make glass.

Halls says: "My most striking memory of Jimmy is his determination to make me catch a salmon. He tried several times without success. Finally, he took me to a loch in the wind and rain, and pushed off with such force that he snapped both of the rather vintage oar blades. He kept rowing round that loch with just the stubs of oars for seven hours, stopping at all the ideal salmon spots. Eventually the mouth of this enormous salmon yawned beneath me but I got "trout twitch" – I whipped the fly clean out of its mouth through sheer nervous energy and over-excitement. And cold. I thought Jimmy would kill me. But he just shook his head and muttered that at least I'd tried."

For three decades as a ranger and a volunteer, James MacLetchie's job has been connecting amateur enthusiasts as quickly as possible with the wildlife their busy, powerful lives have been disrupted to witness. "I know guides that boast that they can guarantee otter sightings. If it was that easy there would be no joy in the job. The Uists are a wild and untamed environment where nature flourishes. That is what visitors want to experience," says MacLetchie.

Great Hebridean Escape sees urbane explorer Halls become MacLetchie's apprentice. Determined to leave a legacy (and conscious of the plethora of "show and go" TV programmes in remote, fragile communities), Halls aims to recreate the Uist man's old Ranger Service during the six months of his stay. So the six-part series features activities such as fund-raising for signs and tissue-sampling stranded whales. But for the ranger and his apprentice perhaps the highlight was a trip to St Kilda on Monty Halls's own 18ft adapted Rib. The uninhabited island is one of only 25 places to hold dual World Heritage status and lies 41 miles and about four long, cold hours west of the Uist "mainland".

MacLetchie recalls: "I remember when we discussed it I told Monty about the amount of planning that a trip into the raw Atlantic Ocean required and he looked shellshocked. I guess waking up each morning in his cottage and seeing the massive lump of St Kilda loom so close, it probably felt within reach. I talked to some of the regular boatmen who make that journey, then pulled his boat to pieces and gave him a long list of parts, repairs and extras. He didn't argue, went to Stornoway and somehow got the lot.

"The journey there was an epic. With more than two hours to go he thought we were almost there. Finally we headed into Village Bay and the elation was all over his face. He was the first TV presenter to get there under his own steam. We camped overnight and woke to the sound of a gathering wind and the screeching of thousands of gannets. I told Monty that conquering St Kilda involved getting back – in a force six gale. I was standing behind him as we rounded Village Bay into the teeth of a storm and heavy seas. Huge waves were lifting us almost vertical. Monty was trying to hold the Rib while keeping his head and hand on the throttle. One mistake here and it could have been curtains. This was real adventure at the extreme edge of nature, but he held his resolve and got us home in just over three and a half hours. I never saw him for two days after that. I assume he was totally drained from the whole experience emotionally and physically."

Ironically, just weeks after that visit, Halls and MacLetchie discovered that North Uist had missed out on the bid to build the "official" St Kilda visitor centre. So too had Leverburgh on Harris. Instead, the distant Mangersta on the west coast of Lewis had been awarded the contract. Halls observed that this would have been the "2012 Olympics" for North Uist. But once again luck by-passed the southern isle with the longest cultural links and best view of the empty, tragic visitor magnet of St Kilda.

And after six months of hard (televised) labour, there is no plan to reinstate the Ranger Service on North Uist. Crofting communities don't want responsibility for even a part-time wage. Such has been the impact of great visitors, grand visions and harsh reality on the Western Isles over centuries. Both men agree this year is make or break for North Uist as the reduced ferry fares of the SNP's pilot Road Equivalent Tariff (Ret) scheme end in November.

MacLetchie says: "Low fares have to continue, even in a recession. Ret has proved people will come here if they can afford it. Those who predict the island will be overrun with tourists are scaremongering. Any increase in the short tourist season will keep jobs and local people here. Innovation will protect a way of life. The Great Hebridean Escape will encourage people to staycation yet again because of the incredible diversity within our own country."

Monty Halls's sense of responsibility is even stronger.He says: "For the first time ever, the local summer show in Sollas didn't have the traditional shinty match last year. The organiser told me there weren't enough young players to raise a team. The old crofters are watching the population leave and they want a chance to reverse that decline." Perhaps, as the endless white beaches and limit-free living start to roll across BBC screens, television will prove it can heal, advocate and entertain.

James MacLetchie runs www.hebrideanadventures.co.uk

Monty Halls' Great Hebridean Escape is on BBC2 tonight at 9pm.