A solitary blonde figure walks the a 10-kilometre stretch of sand on desolate Koh Phra Thong, an island just north- west of Phuket off the mainland town of Kuraburi. It is hot — very hot, possibly 39 degrees Celsius in the shade — but still the female figure, dressed in T-shirt, long pants and sun hat, continues her walk, taking her time. Every now and then she stops to survey the sizzling beach before moving on.

The figure is Monica Aureggi. The long walk is something she's been doing for a quarter of the year, up to three times a day and often through the night, over the past eight years. Monica is no ordinary visitor to Thailand. How many foreign women come year after year to Koh Phra Thong and spend all their time walking the beaches? After just a few trips, Monica became well known to the Thai local fishermen and the local hotel owner.

She first came to this Andaman Sea island almost a decade ago. Based in Cantu, in her native Italy, she works as a marine researcher specializing in turtle conservation. When she arrived at Koh Phra Thong she immediately recognized the coast as probable nesting territory for turtles. Since only one in 1,000 turtles survives to adulthood, the struggle for survival is tough. On top of that, the seven species of turtles found globally have all been listed as "endangered" by international wildlife conventions. Thailand's turtles include the olive Ridley, hawksbill, green turtle and the leatherback, rated as "critically endangered" in Thailand since 1996.

Knowing well how hard it is for turtles to survive, not just in the Andaman but around the world, Monica was adamant that these quiet ocean creatures should be given a chance to reproduce on Koh Phra Thong. Too many times she has seen how, on the Greek island of Crete, for example, rows of beach umbrellas and chairs have discouraged turtles from coming ashore to lay their eggs. On her daily beach patrols, Monica seeks signs of nesting or hatching, notes them, and relocates the nest if it's in danger from flooding, poachers, animal predators or tourists. Over the years, she has spent much time and money in helping with what may finally prove to have been a Quixotic struggle to save the turtles of the Andaman Ocean from extinction.

Thailand's turtles have long been under threat. The beautifully marked shell was for centuries a highly-prized material. Today, its import and export is outlawed by many countries. Turtle eggs are also a valuable commodity, considered a gastronomic delicacy in some parts of the world and prompting poaching from nests. Humans top the list of the turtles' natural predators, however, more of a threat than dogs, birds and crabs. Encroachment from new buildings — any kind of noise or lights, including distant airport and plane landing lights — or the use of very fine fishing nets seriously hinders turtle reproduction. On the Greek island of Kefallonia, locals were so adamant that their much-loved turtles should be protected that, when it was suggested that cheap European charter flights fly into the island at night close to nesting areas, the whole island protested, knowing that the dazzling runway and aircraft lights would drive the turtles away.

Uncontrolled beach development is one of the most obvious problems, nowhere more so than in Thailand, where Monica has seen beaches on nearby islands transformed from peaceful nesting grounds into concrete jungles, — new resorts for tourists eager to enjoy so-called eco-tourism. Monica set up the Naucrates charitable organization in Italy in 2001. It operates as a non-profit charity aimed at conserving the last few populations of turtles, focusing on education and local community involvement. Members pay 25 euros to join and 20 euros to sponsor a turtle.

Monica usually arrives late in the year at Koh Phra Thong, taking up the post of turtle-centre custodian till the end of March. Drawing on very limited public donations, she publishes Sea Turtle Times, a quarterly pamphlet detailing the efforts of the charity, both victories, such as releases of rehabilitated creatures, and disappointments, for instance when a sick turtle cannot be saved. It also updates research and sightings connected with other marine wildlife, including the beaching of a rare Risso's dolphin on Karon Beach and a new mangrove research project.

Monica is not alone on Koh Phra Thong. A small band of eco-volunteers, mostly from Europe, arrive each season to help. They live in basic conditions on this isolated island from November to March. Their routine at the Naucrates camp is far from idyllic. It involves many long nights without sleep and bitten by flies waiting for the visits of nesting females. And scrubbing a turtle pool coated with turtle excrement is no easy task in daytime temperatures of 35 degrees Celsius upwards, all without modern bathroom facilities or mechanical help. During the nesting season, the gruelling, 10-kilometre walks to watch, day and night, for signs of life must be assigned by roster.

The volunteers are carefully trained; among other things they use red filters on their torches to avoid alarming the pregnant reptiles. At regular intervals during the heat of the day someone has to climb a steep little cliff to survey a rocky bay where feeding turtles have been sighted. At the top, a pavilion provides welcome shade for volunteers who must then spend an hour or so recording notes of any ocean visitors for statistical analysis. Next door lies the low-key Golden Buddha Resort, little more than rustic beach huts and small Thai wooden houses. The American owner, Richard Sandler, generously allowed Naucrates to appoint their cluster of grass huts and "Baan Tao", a tiny information centre, in these grounds. Guests are encouraged to pay the centre a visit free of charge. The natural history exhibits include specimens of local reptiles in bottles, turtle skeletons, egg shells and some formalin-preserved marine life.

Most people know little about the gentle sea turtle. Few people realize that the sex of the incubating turtle eggs is determined by the temperature of the surrounding sand — the hotter the sand, the greater proportion of females will be born. Near one of Phra Thong's beaches lie two holding ponds for sick turtles. It is around these that Monica's Naucrates team perform their turtle-keeping rituals: daily feeding at 5pm; emptying and scrubbing of the pools every two days; and regular health checks and medication, including body measurements and weight checks.

The patients are brought over from the Marine Biological Centre on Phuket. Many have been found caught in nets, their fins shredded. Others have been kept in captivity by former owners who had no knowledge of their needs; and, as a result, many turtles arrive suffering from lung disease from living in poor water conditions. Some are more fortunate. In February, three small 18-month-old turtles were part of a release ceremony attended by many of the hotel's guests. The three turtles had been held until they had recovered from net lacerations and were of a size and maturity that Monica felt gave them a better chance of survival. That evening, three young marine reptiles got their first breath of freedom as the crowd quiet- ly watched them scuttle towards the sunset and into the surf. A rousing cheer went up as they disappeared into the sea.

There are other successes. The following circular went out in 2004: