Sorry, the rudder's broken," said Clayton, a young South African from Pretoria. "We'll have to take the speedboat." Donning life jackets, we jumped out of the large, slick transfer boat that takes passengers from the small jetty at Marsa Jebel Dhanna to Sir Bani Yas Island and hopped into the smaller vessel for a rough, 10-minute crossing with waves crashing across the prow and water leaking through the windscreen. We didn't mind - arriving was far more exciting this way. It had been a three-hour drive from Abu Dhabi along nondescript roads. Yet the salt flats around Jebel Dhanna - themselves at least 4,000 years old - have yielded fossils from a much earlier age. Here, 240km west of the capital, the expanse of white sabkha between the sea and the road to Sila is the only visible clue to the area's ancient past. Jebel Dhanna, one of the few topographical features, isn't really a mountain, a hill or a slope - it's a salt dome, one of a series created millions of years ago, before the Gulf as we know it today was formed. Eight kilometres offshore, Sir Bani Yas Island - the Sir is pronounced "seer" and means hereditary or high rocky place - contains several peaks at its centre which are also salt domes -dating from the Cambrian period some 600 million years ago. Sir Bani Yas only became an island at the end of the last ice age around 10,000 years ago: it was the end of a 10,000-year period of low rainfall and desertification which marked the beginning of the end for the area's wildlife. Yet around eight million years ago, Abu Dhabi's Western Region looked much like East Africa or the fertile Nile Valley. Crocodiles and hippopotamuses thrived in its slow-moving rivers and dense mangroves, while in its lush savannahs, three-toed horses, four-tusked elephants, ostriches, giraffe, herds of antelope and hyenas roamed. But by 3,000 years ago, after the Stone Age, even the gazelle, oryx and ibex were beginning to decline, and by the 1960s, thanks to hunting, the Arabian oryx was extinct in the wild. Over 17km long and nine kilometres wide, Sir Bani Yas is the UAE's largest natural island - at 87 square kilometres, it's slightly bigger than the island of Abu Dhabi. It has been a breeding centre and wildlife reserve since 1971, established by Sheikh Zayed and widely credited with the rescue of the Arabian oryx. A successful breeding programme has yielded today's herd of around 500 healthy animals, the highest single population in the world. Already, some have been released into a new, 9,000 square kilometre reserve in the Liwa desert. As we drive across the island in an open-topped vehicle, Clayton, our guide, explains that the Arabian mountain gazelle and the sand gazelle that are found in the island's new 4,000-hectare Arabian Wildlife Park have adapted to desert environments by secreting less water, and that all three species of oryx on the island - the Arabian, beisa and the huge scimitar-horned variety - raise their body temperatures to prevent sweating. "See, the Arabian oryx appears white but if you look closely you can see that the skin below the hairs is dark. So the hairs reflect the sun, but the skin below acts as a barrier." The running of Sir Bani Yas was taken over by the Tourism Development and Investment Company (TDIC) in 2007, and opened fully to the public last year. In the next six years, TDIC aims to make it and the seven islands surrounding it - branded as Desert Islands - a major draw for both domestic and international tourists. Some 5,000 tourists have already visited and Clayton is one of 14 guides recruited from all over the world to work here; a training centre on neighbouring Dalma island is currently preparing a number of UAE nationals to join the fray. As a naturally barren island which has been cultivated with 2.5 million small trees planted in mostly straight rows in the sand, connected by kilometre after kilometre of black water pipes and a tarmacked road system, it isn't the most visually stunning of islands (the surrounding islands, including Discovery Island, which is completely uninhabited and will be used for snorkelling excursions, look more exciting), but that, according to Desert Islands' marketing manager Lars Nielsen, isn't the point. "We don't want people to come here thinking it's a beautiful undisturbed island. There is a greater purpose to this island." Indeed there is. Sir Bani Yas is the only place in the world where I've come face-to-face with a Barbary sheep - first one, then a large herd. Led by Clayton, we disembarked the game drive vehicle near the 130m-high salt domes in the centre of the island. We crossed Wadi al Milh - filled with extensively mined rock salt quarries, looking for Africa's only wild sheep. They are partial to the taste of salt, so Clayton was sure we'd find them here. Having an uncanny knack of blending into their surroundings, spotting them was at first difficult, and when we did, our loud steps on the crumbly surface sent them bolting in unison. We went back around the corner and waited. Then, suddenly, there they were: as inquisitive as they are skittish, several dozen of these extraordinary animals had snuck around the side of the salt dome and gathered across a small ravine, staring intently at us. We froze, wary of scaring them. Bizarre creatures with enormous, wildly-curving horns sprouting from just above the ears and long, flowing chest hair, they are more goat- than sheep-like and at once long-faced and comical. They are able to survive in rocky, waterless environments - usually in North Africa - by living on the moisture found in mountain plants. The Barbary sheep, like the much smaller sand gazelle, is classed as "vulnerable" in the wild by the International Union for the Conservation of Nature. That's only one category below endangered, but here the Barbaries, like most of the other animal species, enjoy a constant supply of food and the attention of vets. The Arabian Wildlife Park covers the large, central portion of Sir Bani Yas and is described by Desert Islands as "an Arabian Ark in the making". The park's fencing and road system will be finished by the end of this year, and the aim is to house thousands of free-roaming native species and a handful of predators and scavengers, providing a wildlife-watching experience unlike any other in the Middle East. The predators are there to introduce a degree of natural selection to the populations of smaller animals. In May, a three-year-old cheetah was let loose in the park; there are also four striped hyenas and two more cheetahs will follow. Since my first visit to the island last year, some 10,000 animals - half the total number - have been moved to reserves on the mainland in a massive effort involving the Abu Dhabi Environment Agency and Sir Bani Yas' own conservation department. Some 400km of fencing has also gone, and it's all to the good. There is more vegetation and less overcrowding, and the number of non-native animals - never a good indicator of sustainable wildlife management - has been substantially reduced. The remaining inherited, non-indigenous animals such as red deer, llamas, Indian antelopes and 39 giraffes, are kept in spacious enclosures outside the Arabian Wildlife Park. "Although our main focus is indigenous animals, the other animals are part of our history and we don't want to get rid of them completely," says Nielsen. Desert Islands aims to be a "sustainable" operation and is developing an alternative energy plant on the island - already there is one wind turbine which provides two per cent of Sir Bani Yas' power, and there are plans to harness solar energy. It's hard to see how an island that uses between eight and nine million litres of desalinated water per day (that's nine billion litres a year) - not to mention demanding a three-hour drive or 40-minute flight to the island in a small aircraft - can be described as sustainable, but again, Lars Nielsen is sanguine. "Water consumption has already been cut by two or three million litres a day over the last three years. We have changed the level of irrigation in some places - we are watering less or in some areas not at all - and further irrigation trials are taking place." Though it has only ever had a limited amount of fresh water, Sir Bani Yas is thought to have been inhabited since around 7,000 years ago, as flint Stone Age tools have been found in the north and the remains of a Bronze Age structure has been discovered near the airport. Pottery from Mesopotamia found on other islands including Dalma - which has a more plentiful supply of fresh water and has been inhabited for at least as long - suggests a history of trading with Iraq. There are more than 40 archaeological sites on Sir Bani Yas, including a 1,500-year-old Nestorian monastery and a 300-year-old mosque. A partnership between TDIC and the Abu Dhabi Authority for Culture and Heritage (Adach) will see some sites open to the public next year; in the future, visitors will be offered archaeological tours. While Sir Bani Yas may not be as untamed as an African safari, the island is a welcome break from the city. Largely free of buildings, there are pockets of the place - the mangroves on the north-eastern shore and the lake just behind the new Anantara hotel - that resemble wilderness. At present the 64-room Anantara Desert Islands Resort & Spa, situated on the northern shore, is the only hotel; coming developments will bring another 200 rooms in four small five-star lodges by 2011 and around 1,900 more rooms by 2015. There will also be an equestrian centre with Arabian horses, a diving centre and, in the future, some exclusive, Maldives-style rooms on two of the small islands. I longed to put on my snorkel and disappear under water, as the reefs surrounding the islands are said to be stunning, with sea turtles, dolphins and fish protected by a no-fishing zone, but conditions were too rough. I wanted, too, to kayak around the most beautiful mangroves, but again, choppy waters prevented it. After two days, we took off in an eight-seater Cessna Caravan from the island's airport (a modern passenger terminal is still under construction) and headed east back to Abu Dhabi, flying low over the hundreds of uninhabited islands that dot the coast: vast areas of shallow water cover turquoise reefs with only the odd small boat to be seen. For visitors to Abu Dhabi's desert islands, it seems, the best is yet to come. rbehan@thenational.ae