On Monday morning, when Goran Susic turns up for work, he'll do an unusual thing before reading his post and emails. His first duty will be to check on the condition of a griffon vulture that was rescued from the sea on the point of drowning. She is being nursed back to health at his Eco-Centre. The centre, founded by Goran 16 years ago on the island of Cres in Croatia's northern Adriatic, is dedicated to the preservation of nature.
The female vulture was brought in having swallowed some poison probably laid as a trap by a farmer, but is recovering well and shows every sign of attaining adulthood. By then, her wings should span more than 8ft, capable of propelling her through the sky at speeds of up to 70mph, more than a mile higher than any other bird, in temperatures as low as –60C. For a year or two she might venture as far as Greece or Israel, before returning home to nest on a near-vertical cliff in the north-east of Cres. There, she will select a mate, and remain for up to 60 years – unless mankind messes up her life again.
Separated from the mainland when the sea rose 20,000 years ago, Cres is a long, thin strip of land with forest in the north, a barren plateau in the south and a large, freshwater lake in the middle. While the neighbouring islands of Losinj and Krk have been extensively developed, Cres has been left alone: it has only two hotels, and there are fewer than 3,000 permanent inhabitants straggled across its top-to-toe length of 40 miles. Nature has room to breathe – and the scarcity of humans gives the vultures a fighting chance.
The more adventurous variety of humans will have a field day here, too, because Cres in the summer provides excellent terrain for walkers, ornithologists, and whatever you call people who are content to spend an entire day in the wild without encountering another living soul. The only place resembling a town (also called Cres) is as good-looking as the rest of the island, with a maze of higgledy-piggledy lanes and surprising Italianate piazzas, amid the pastel houses that glow in the late afternoon as if ripening in the sun. The hill villages of Beli and Lubinice, the latter atop a 1,250ft west-facing cliff, are also breathtakingly beautiful.
Hotels may be thin on the ground, but comfortable accommodation is widely available all over the island, if you don't mind sharing the odd bathroom, doing your own catering or dining with the hosts. That said, I spent three memorable nights at the Pansion Tramontana in Beli, where every bedroom has an en suite bathroom, the pub grub was beyond reproach, and the bar stayed open far longer than was sensible.
Twenty-five years ago, on a casual visit to Cres, Goran Susic experienced a life-changing moment as he observed a griffon vulture in flight. "It was like poetry in the air," he recalls, "as it angled its wings into a gale strong enough to knock a human over, while seeming to be totally unaffected by it. Watching this bird fly gave me an understanding of how nature works so perfectly."
They're a rare sight in Europe these days. There are griffon colonies in the mountains of Spain and Greece, but the great bird has almost disappeared from central and western Europe, unable to adapt to man's changes to the ecosystem. And then there are the day-tripping tourists who are taken on boats to a point immediately below the vultures' eerie, and make as much noise as possible to encourage them to fly out for a photo-shoot. The din frightens the birds, who sometimes take off when there's insufficient wind to support their weight, and fall into the sea. Unable to fly because their giant wings become saturated with water, their chances of survival are slim.
Nevertheless, thanks to the efforts of Goran and his team, Cres remains one of the griffons' last redoubts in Europe. When he began his work, there were fewer than 50 on the island. Now their population has swelled to 140, paired off in two colonies.
With the knowledge and contacts that came with his PhD in natural sciences, Goran resolved to protect the endangered birds. He gave up his desk job on the mainland to visit the island as often as he could, sometimes sleeping on beaches or in the forest, parts of which have lain undisturbed for a millennium. There, he discovered rare flora and fauna, long-dead medieval villages, and the ancient remains of mysterious settlements and temples that still defy scholarly explanation as to who constructed them and why.
As a result of Goran's efforts, Cres was declared Croatia's first officially designated "eco island" in 1986, and seven years later he set up his HQ in a disused school near Beli, a tangle of narrow streets and squat houses that you reach along a cobbled Roman road, with grass growing between the stones.
The new centre was given the Latin name of Caput Insulae ("head of the island"). So far, the project has attracted more than 12,000 volunteers from around the world. They stay for anything up to three months, paying a nominal sum for their board and lodging, and performing tasks as menial as cleaning out the birds' enclosures, and as unusual as making regular deliveries of sheep-meat to a platform on the cliffs above the dazzling Adriatic. "The Vultures' Restaurant", as it's known, ensures that they all have enough to eat.
Other volunteers show visitors around the centre and maintain the ancient pathways into the untamed forest. From these, Goran has created seven looped walking trails, varying in length between a mile and six miles. The signposting is excellent, and the paths have enticing names such as Elf Trail, Fairy Trail and Orchid Trail. They wind through a landscape of olive, oak, fig and pomegranate trees, ancient dry-stone walls and the ruins of long-abandoned smallholdings.
One path drops below the village to the river, forded by a 1st-century Roman bridge, still wholly intact. Another route is way-marked by 20 modernist sculptures, done in white marble by a renowned Croatian sculptor. On the way, Goran points out an oak tree intertwined with ivy, both of which have outlived their normal span, disproving the commonly held belief that ivy is a parasite that kills its host.
Cres is like nowhere else. For some reason that may or may not be connected with the fact that it lies astride the 45th parallel (halfway between the North Pole and the Equator) the island has astonishing bio-diversity. It boasts more than 1,300 native plant species (nearly as many as the UK in an area smaller than the Isle of Wight), including 42 types of orchid and 60 species of butterfly. There is much to lose if nature's delicate balance is disturbed, even slightly.
"I want to create an island that produces its own organic food – plants, herbs and responsibly raised cattle – with no additives," says Goran. "To market this unique place we need to attract fewer day-trippers and more eco-tourists – walkers, cyclists, bird-watchers, even meditation groups. The mass tourists, who sail over every day in summer and lie on the beach, leave nothing but garbage."
Disposing of litter is another of the Eco-Centre's task, and slowly the battle is being won. Another challenge is being posed by wealthy hunters, who've annexed a portion of the forest and introduced wild boars for sport. One afternoon, our progress along a lonely track was abruptly halted by a high fence and "Keep Out" signs in forceful Croatian. "The vulture colonies would now be self-sustaining but for these people and their poison traps," said Goran. "They want me off the island," he added, "but I still have work to do."
On my last day, as I drove to the ferry for the short crossing back to mainland Croatia, the weather took a turn for the worse. A high wind and horizontal rain buffeted the car. Suddenly, through the window, I caught sight of a large, dark shape in the grey sky, angling its wings to harness the forces of nature in wide, sweeping circles of smooth and glorious flight. God speed to the Cres vulture, master of all it surveys, but forced to rely on the efforts of a singular, driven man for its continued existence.
The two nearest airports to Cres are Pula and Rijeka, both within easy reach of Cres by ferry. From May to October, Croatia Airlines (020-8563 0022; croatiaairlines.com) flies to Pula from Gatwick and to Rijeka from Heathrow.
Two low-cost carriers have summer services to Pula: Ryanair (0871 246 0000; ryanair.com) flies from Stansted; Flyglobespan (0870 556 1522; flyglobespan.com) from Edinburgh.
To reduce the impact on the environment, you can buy an "offset" through Abta's Reduce my Footprint initiative (020-3117 0500; www.reducemyfootprint.travel).
There are regular car ferries to Cres from Brestova on the mainland (20 minutes) and Valbiska on the neighbouring island of Krk (30 minutes). There is also a passenger-only catamaran from the mainland port of Rijeka (75 minutes).
All the routes are operated by Jadrolinija Ferries (00 385 51 666 111; jadrolinija.hr).
Pansion Tramontana, Beli (00 385 51 840 519; beli-tramontana.com). Double rooms start at €70, including breakfast. Evening meals are also available.
The Eco-Centre Caput Insulae in Beli (00 385 51 840 525; supovi.hr) is open to the public and volunteers between 1 March and 31 October. Admission €3. The website has information about the volunteer programme.
Cres tourist information: 00 385 51 571 535; tzg-cres.hr.
The Croatian National Tourist Office, 162-164 Fulham Palace Road, London W6 (020-8563 7979; croatia.hr).