Where Darwin evolved the big theory

The sun rises at 6am in the Galapagos Islands - a little late by British summer standards - but at least you can be sure it will rise in a blaze of glorious yellow. Pelicans will be sitting patiently on the dinghy bobbing behind your boat, waiting for morsels of lisa fish to be tossed out as the captain guts the early morning catch in preparation for lunch.

This is the way to see the Galapagos - on a small boat, sailing between the islands. You wake up to a new vista each day, and fall asleep under a sky thick with stars, with sea lions grunting on the rocks outside your porthole.

If you love wild places, and especially if you love wildlife, you will see why the first explorers to land here called this place las islas encantadas - the enchanted islands. Windswept cliffs are home to 58 species of birds, 28 of them found only in the archipelago. On one clifftop on Espanola island we watched giant albatrosses stepping off into the air currents and floating down above the waves.

To get there we had climbed up through brushy scalesia trees and scrambled past a colony of about 400 blue-footed boobies, all nursing offspring or squatting on eggs. Otherwise pale and unassuming, these bird have the most extraordinary webbed feet of the brightest midnight blue, and the males employ them as a seduction technique. A male will stand very solemnly, lifting one leg at a time. Judging by the number of offspring here, the technique is pretty successful. Each pair raises two chicks a year, and our trip in late May was a perfect time to see young ranging from one-day old to two months. The parents take turns to sit on the hatching eggs in regular, 12-hour shifts.

More entrancing, though, are the sea lions, which you smell and hear long before you see them.Basking in the sun, they snooze in vast numbers on the sand or rocks, curled up together with their heads on each others' flanks. Young pups waddle up for a closer look at you and to nibble your toes, shying away only when the 500lb dominant male comes roaring out of nowhere to bring them back to the fold. One of the greatest delights here is swimming with the pups, although the first time a sea lion darts up to peer at you through your snorkelling mask is disconcerting.

The snorkelling here is fantastic; even without the joy of the sea lions, there are angel fish, parrot fish, Moorish idols, "chocolate-chip starfish", sharks (small ones), leather-backed turtles, rays of every hue - golden, black and white-spotted - and the giant manta, which can grow to a fin- span of 18ft.

Our enthusiasm was matched only by that of our guide, Luis, who remained unwearied by months of seeing familiar creatures. "Look, look, an iguana," he would cry, prompting us all to dash over the rocks brandishing our cameras like paparazzi descending on Liz Hurley. I wondered how I would manage, seven days a week, keeping excitement in my voice as I shouted "Look, look, a dog!"

During a week here you can visit roughly seven islands, although if you can manage a fortnight you will get to visit some of the more outlying islands where whales are more likely to be found. Sailing never takes up more than a couple of hours a day, but, in any case, the voyages are a good time to sunbathe and scan the horizon for dolphins. Our vigilance paid off one day when we were joined by a school of dolphins, diving across our bows and each other.

During your trip you also visit the Charles Darwin research station, which is responsible for the protection of the islands and their wildlife. It also advises the Ecuadorean government on environmental matters, rears endangered giant tortoises (Steven Spielberg must have come here for inspiration for ET) and provides a home for Lonesome George, the last remaining Pinta tortoise.

Visitors, they say (contrary to expectations), are not the greatest threat to the islands. "Tourism is almost more the solution to the islands' problems, since it provides economic activity for local people," says Julian Fitter of the Galapagos Conservation Trust, a charity based in Shaftesbury, Dorset, which raises funds for the Charles Darwin Foundation. Numbers so far have been carefully controlled, which means the animals and birds can remain unafraid, and it also means you never feel that the islands are swamped with people. In fact, you hardly see another soul. Of the 61 islands in the archipelago, only five are inhabited.

According to Mr Fitter, the main problem is introduced species. Settlers brought with them goats and dogs and pigs, against which endemic plants and animals have no defences. Goats have deforested large areas, wild pigs eat bird and turtle eggs, dogs kill land iguanas and turtles. One of the research station's biggest tasks is to control the numbers of introduced species, and in some cases, such as the goat population on Pinta, to eliminate them altogether. "There is no point worrying about the effects of tourism if the introduced species are not controlled, because in 50 years' time they will have taken over - there will be nothing left," Mr Fitter says. In the meantime, it seems that tourists are welcome. Luis Maldonado of the Association of Galapagos Tour Operators says: "The present capacity for tourists is almost double the actual flow, and if tourism is handled well, as it has been for the past 25 years, it allows sensible use of resources and brings increased awareness of the islands."

When to go

From the end of December to the end of March is warm and calm. July to December is mistier and drizzly; September is particularly drab, and is best avoided.

How to get there

Get to Quito, the capital of Ecuador; South American Experience (0171- 976 5511) has a fare of pounds 447 on Viasa from Heathrow via Caracas. From here, two airlines (TAME and SAN) fly to Baltra and San Cristobal respectively for pounds 200-pounds 250 return. The Ecuadorean Air Force operates Hercules freighters to the islands.

What to sign up for

You can select an eight-day boat trip or stitch together two four-day ones. Total cost can be anything from pounds 600 to pounds 1,800. A hotel / cruise combination costs as little as pounds 450.