In Sichuan province's Wolong Nature Reserve, the happy panda is all-pervading. The stuffed toys and key rings at the centre's souvenir shops, the panda logos on travel brochures, the cartoon figures on postcards - these bears always wear a smile. But a close look at the life of the captive pandas at the reserve suggests some of them may not be as happy as they should be. Within Wolong, the world's largest panda reserve and probably the best known in China, 53 captive animals sleep, eat, rest and breathe clean air. While wild pandas are threatened by habitat encroachment and forest destruction, those in captivity in Wolong appear to have nothing to worry about. Their home is a huge park managed by the China Conservation and Research Centre for the Giant Panda (CCRCGP). The complex forms part of a larger reserve, measuring 200,000 hectares and nestled on the slopes of the lush Qionglai Mountain, in the middle of Sichuan. Surrounded by picturesque valleys and calmed by the gurgling of a limpid river, the reserve is also home to 110 rarely seen wild pandas. It is one of the few places in China where the winter air is not tainted by burning coal; the scent is of trees and the moon shines brightly through a clear night sky. Seventy CCRCGP staff members care for their charges, feeding them six or seven times a day. Within walking distance of their grass-covered residences, a veterinary clinic manned by well-trained vets working 14-hour days is at the pandas' service. The clinic has recently benefited from a renovation, thanks to $1 million of funding from the Ocean Park Conservation Foundation Hong Kong. Lavish care and improvements in conservation methods have led to a thriving panda population in Wolong in recent years. Last year, a record (in the CCRCGP's 22-year history) 16 cubs were born from 11 births, through natural or artificial insemination, significantly increasing numbers of a species renowned for its lack of fertility and low reproduction rates. According to official census findings released in 2004, there are about 1,600 giant pandas in the wild in China, compared with 1,100 in the 1970s. Another 166 pandas live in captivity. 'We have made impressive headway in the wellbeing of the pandas over the last two decades,' says CCRCGP assistant director Tang Chunxiang. 'Our pandas are very happy.' Despite Tang's assurances, however, some of Wolong's pandas display behaviour that suggests they are far from happy; they seem bored and apathetic - and that puts into doubt their prospects for integration into the wild. You You is one such panda. She often performs a repetitive sequence of aimless movements prompted by boredom and a lack of stimulation from the external environment. Animal experts believe such behaviour will weaken affected pandas and poor mental health will undermine the animals' prospects of returning, or being introduced, to the wild - the ultimate goal of conservation. Preoccupied with herself in an open-air, 800-square-foot enclosure, You You lives a few blocks from four cubs that like to frolic. Although she can, if she so desires, wander over to her neighbour through a round opening, she seems to prefer her own turf, lying on a wooden platform supported by a tree trunk. Her breakfast is served daily between 10.30am and 11am. On hearing the footsteps of the keeper, You You climbs down from her tree trunk with the dexterity of a fireman sliding down a pole as sticks of bamboos are laid out before her. After an hour of feasting, the seven-year-old begins to pace up and down her enclosure in a seemingly mechanical fashion. The path she takes is more or less the same every day and she remains expressionless throughout. The novelty of her 'toys' - a few branches and a metre-high wooden platform - has worn extremely thin and occasionally, You You just stops and sits, staring blankly through the glass barrier that separates her from visitors. Sometimes, she'll bite her feet, rock her head slowly or look heavenwards, as if contemplating a deep philosophical question. For the enthralled visitors, numbering 50,000 a year, the scene is a great photo opportunity. 'So cute,' a visitor says as she happily snaps a photo of You You. 'I like the way she walks. She wags her cute bum. She just keeps walking back and fro.' For animal experts, however, You You's behaviour is not so cute. 'Some of the pandas here exhibit behaviour we never want to see in An An and Jia Jia,' says Timothy Ng Sau-kin, assistant director of zoological operations and education at Ocean Park, referring to the two pandas given to the park by the Chinese government in 1999. 'So far, under our care, we have not seen An An and Jia Jia display [such] behaviour. Every week, we give them stimulating items, such as frozen food, a sac bag [a small, stuffed linen bag], different scents and shredded paper.' Tang acknowledges that some of Wolong's captive pandas are displaying signs of boredom, but stresses it is not a serious concern and no injury has occurred. 'Some pandas do have bad habits. They may pace or shake their head, but it's not a serious issue and it takes time to get rid of bad behaviour,' he says. 'They are very healthy.' According to Ng, who organises husbandry and animal-behaviour workshops for CCRCGP staff, meals should be placed at a considerable distance from the animals, thus developing in them an ability to search for food. This does not happen at Wolong; the animals have their food placed before them. 'We have politely advised them on ways to feed the pandas. But whether they take the advice or not, it's up to them,' Ng says. 'They're experienced with pandas and we don't want to act like we are being patronising.' Ng adds that an environment devoid of stimuli - especially when the animals are not required to look for food - will induce repetitive behaviour. 'Some types of stereotypical behaviour in [confined] pandas can be invasive, such as biting their own foot or palm, which can induce injury and severe infection.' Ronald Swaisgood, an animal-behaviour specialist involved in panda conservation at California's San Diego Zoo, in the United States, says such behaviour 'represents an obstacle for an animal to return to the wild'. However, the scientist, who has been working closely with the CCRCGP for 10 years, says the health of the captive pandas at Wolong has significantly improved over the past decade. 'Ten years ago, some animals had problems. Staff at the Wolong centre worked very hard to create a better environment for them,' he says. 'Behaviour can be a scar of the past. Although the environment can be quite good, [the repetitive] behaviour is wired into the pandas' brains. It takes time to correct them.' So far, none of the pandas born at the Wolong centre has been introduced into the wild, although staff plan to set free at least one such animal this year. 'Bringing them to the wild is the whole point of the conservation work,' Tang says. 'It is a big challenge for us. There're a lot of uncertainties. We don't know whether they can look for food, build a family or defend themselves from enemies.' To prepare for a panda's integration into nature, Tang says, a number of measures are put in place. Feeding schedules are changed to prevent the pandas from taking their meals for granted and enclosures - one of which incorporates features designed to imitate the forest - are swapped every few months. Researchers have also tried to stimulate the pandas with tree branches, tyres and a small rocking horse, but their appeal for the animals has apparently faded. Recently, Ocean Park, which regularly sends staff to train counterparts at the CCRCGP, sought to spice up the lives of Wolong's captive pandas by sponsoring the Enrichment Items Design Programme. The nine-day programme involved students from the University of Hong Kong and toys they had designed specifically for the purpose. Environmental life science students Vivien Bao Weiwei and Angela Lam observed how pandas responded to a number of toys and 'enrichment' items, which included a sac bag and a carefully painted tube that contained food. One of the guinea pigs in the test was Lin Lin, an eight-year-old male who has often been seen pacing his four-metre-wide enclosure. His behaviour showed signs of improvement with the introduction of the novelty items. 'For the first couple of days, he appeared hesitant with the toys,' says Lam. 'Then he got used to them and became more and more excited. He would wipe the sac bag on his face and he knew how to shake the tube to get the food to come out.' The students say they detected problem behaviour in about a dozen of Wolong's pandas. 'I saw one of them stand up and face the wall after eating. A few others kept pacing or sticking out their tongues, which could be signs of boredom,' Bao says. Huang Zhi, manager of Wolong's breeding centre, acknowledges the importance of stimulation but says, 'We don't have enough manpower. At Ocean Park, each panda is looked after by two keepers. Here, the ratio is two pandas to one keeper. Sometimes it's three to one. We try to play with them, but we don't have enough people.' 'We're very busy here. It's very hard work,' says a flustered He Yongguo, a breeder in Wolong's infant department. The 27-year-old Sichuan native is, in a sense, the father of the 16 bears born last year. He stayed up throughout the first three nights of each newborn's life to help with feeding. In August, when his wife was giving birth to the couple's first child, he was preoccupied with feeding a dozen panda cubs. '[My wife] complains sometimes, but there's nothing I can do. There is enormous stress from the job. The party leadership has trusted me with the responsibility of taking care of the pandas. We have had a 100 per cent newborn survival rate for five years in a row and we must go out of our way to keep that record.' Since joining the CCRCGP six years ago, He has lost 10kg in weight and a lot of hair due in part to frequent night shifts. He sleeps six hours a day and works six days a week; sometimes seven. In return, he earns about 1,000 yuan a month. 'There's a lot of satisfaction from seeing the pandas grow up, but then 1,000 yuan is very little money,' he says. As his health is deteriorating, the soft-spoken He says he is unsure whether he will stay in the job for much longer and admits the centre has difficulty attracting young talent. 'Since I started the job, about 100 people have left the centre. Not many young people can stand the hard life here. The weather is freezing in winter and sunshine is scarce throughout the year. There's not much entertainment either. If you want to go shopping, it takes you three hours to get to the town. If you're ill, it takes you three hours to get treatment,' he says. Not long ago, He suffered from gallstones and badly needed an operation. 'I was in pain for three hours before I arrived at the hospital.' Huang echoes He's words. 'Life is hard here and the pay is low. It's hard to attract the country's top talent. We compensate for that by giving a lot of on-the-job training to new recruits,' he says. 'Besides, everyone here is full of passion for the pandas.' A case in point is keeper Li Caiwu, who joined the centre six months ago after having completed a degree in veterinary medicine. 'I came here just for the pandas. I want to make some contribution,' says the 24-year-old, who spent the Lunar New Year at the centre. 'We can only return home for New Year once every seven years. And I'm ready for that.' According to Huang, the only way to alleviate the workload and improve the pandas' mental well-being is to increase the centre's workforce. 'But that's not for us to decide.' The physical well-being of the pandas and their fertility rates are uppermost in the CCRCGP's considerations. Over the past two decades, the centre has been trumpeting its scientific and technological achievements. Founded in 1983, following a massive die-out of bamboo, the centre celebrated its first surviving birth in captivity in 1991. Soon, machines imported from the US were installed to analyse panda hormones in an attempt to boost fertility. In 1997, researchers developed high-fibre 'leaf-eater' biscuits to replace milk and porridge, which often caused sickness in pandas. In 2000, 10 cubs were born, all of which survived, a record that was surpassed only by last year's bumper crop. Official campaigns to revive the nation's declining panda population began in the 50s. In 1958, the Wolong reserve was set up, but wasn't particularly successful because its employees were inexperienced and possessed insufficient knowledge in ecology. In the 90s, however, the situation began to change for the better. Some residents living in the Wolong reserve were relocated, while those who remained were encouraged to grow bamboo and sell it to the CCRCGP for panda food. Electricity costs for farmers in the region were halved to wean them off coal, the burning of which pollutes the reserve. In 1984, to raise more funds for conservation work across the country, China began to offer giant pandas to other nations on 10-year loans. Standard loan terms include a fee of up to US$1 million a year. The money is earmarked for conservation work in the wild and the improvement of the mainland's 40 panda reserves. According to the China Internet Information Centre, about 25 pandas were loaned to nine countries, including the US and Japan, between 1953 and 2000. Compared with the survival of an endangered species, the pandas' mental health seems a minor issue but, Zhu warns, 'If a captive panda lacks stimulation for a long period of time, its mental state is not good and it will be vulnerable to life in the wild.' Back in Wolong, You You has finished her lunch. She resumes her habit of pacing about before sitting down. Another tourist, captivated by the panda's baby-like cuteness, snaps another shot of her, thrilled the subject is so obliging.