Notebook: All creatures great and small PANDA for breakfast? Don't mind if I do. It is a little after 9am, and Tian Tian and Yang Guang, the superstar pandas of Edinburgh Zoo, are preparing for another day - their 413th - dozing and lollygagging in the public eye. Already this morning, Alison Maclean, head keeper of the pandas, has checked on her charges, cleaned out their separate enclosures, gathered and weighed their poo (around 25 kg between them) and now here she is, fetching in great armfuls of fresh bamboo, a plant they eat in enormous quantities, and which is flown in each week from Amsterdam. Nothing is too good for these young bears. In 2011, with the pandas arriving right at the end of the year, the zoo attracted 536,000 visitors; in 2012, that number had risen to just short of 811,000. This is Edinburgh Zoo's centenary year, with the actual 100th anniversary of the 1913 opening on 22 July. Over the decades, the stars of the zoo have varied - like politics or pop music, you only get so long at the top. In the early years of the zoo, the most celebrated creatures were the penguins, the first of which arrived at Leith docks on a Norwegian whaling vessel on a cold day in January 1914. In 2008, with the opening of the state-of-the-art Budongo Trail enclosure, the penguins were eclipsed by chimpanzees. The reign of the chimps was brief, however, and since December 16, 2011, when Tian Tian and Yang Guang went on display, it has been all about the pandas. Working behind the scenes throughout the past 100 years, of course, have been the keepers - some of them stars in their own right, though largely unknown by the public. One such is Alison ­Maclean. An amiable Glaswegian with a broad smile and a slight but appropriate ursine look, she rises at 6.30am each day, perhaps wearing her panda pyjamas, puts on her panda slippers, and immediately checks on the pandas - one is tempted to write her pandas - by logging into her home computer and linking to CCTV cameras. "It is hugely addictive," she says. My husband and I rarely watch telly now. We watch pandas. I don't think I should be paying for a licence any more. She heads a team of four panda keepers and considers it the fulfilment of a lifetime's ambition to work with the animals. There is, of course, a weight of responsibility to deliver a successful breeding programme, but she regards her role as a privilege not a pressure. Although the pandas are a brand and, to mix metaphors, a cash-cow, Maclean sees them rather as two living individuals for whom she is responsible. They have a close trusting bond and come to her when she calls. "I speak to them," she says, "in a Weegie accent" - from which one can only conclude that while they may have understood Chinese when first arriving in Scotland, they now, to paraphrase Stanley Baxter, Pandiamo Glasgow. Edinburgh Zoo is home to more than 1,000 creatures and is set in 82 acres on the southern slope of Corstorphine Hill. In the summer it is hoaching; on the rain-scoured day I visit, less so. Gibbons, high in their enclosure, like look-outs in a crow's-nest, can see the storm clouds pile up over the Pentlands. Far below, drookit school groups trot in their ­wellies in the direction of the meerkats, a mob (yes, happily, that is the collective noun) whose enthusiasm for price ­comparison, or indeed for anything more than sheltering in their burrows, has been dented by the dreichness of the day. Even in such filthy weather there is little for the zoo's keepers to do but get on with their routine. There are worse places to be than the rhino enclosure - a cosy, soupy space, thanks to the warm bath in which the two huge males love to wallow. Steam rises from the great arched back of Bertus as he rises from this tub and heads outside. It is snack time. Karen Stiven, a slender woman with short silver hair and intensely blue eyes, climbs into the enclosure and with great authority and poise hand-feeds the rhino apple and banana, moving him around as if he were a collie dug rather than a two-ton, armour-plated hulk. The trick, she explains, is to be confident and show no fear. She has worked at the zoo for 32 years and rhinos are her favourite. "I love them to bits," she says, patting Bertus's slobbery chin. In the Australian Aviary, Colin Oulton, the 39-year-old team leader of the bird section, is busy scrubbing droppings from the rocks. "This is the glamorous part of the job," he says with a grin. In a minute he will be off to feed eggs to the Egyptian vultures. For the moment, though, as he scrubs, three Victoria crowned pigeons strut around among the foliage. They are the world's largest pigeon, about the size of a cockerel, with a flamboyant crown of peacockish feathers. George Square would be much improved by their presence; better than those scabby doos we have now. Edinburgh Zoo is home to more than 40 species of birds, including the famous penguins; these have been dispersed around the world for the past few months while their enclosure is renovated, but their return is imminent. The most famous penguin of all is Sir Nils Olav, an eminent king penguin with a double life as the mascot of the Norwegian Royal Guard. The most infamous was Asbo, known for pecking the shins of whichever unfortunate keeper was leading the penguin parade that day. What sort of penguin was he? "He was a gentoo," says Oulton. Well, he was a git. Asbo has since left Edinburgh; selected for transfer on the grounds that his particular genetic make-up made him an important addition to a zoo elsewhere, rather than because, as one might expect, his forced deportation was popular among staff. In the long history of the zoo, many other such weel-kent individuals have emerged. The story of Wojtek is well known - a brown bear drafted into the Polish army at the rank of private. ­Wojtek saw action at the battle of Monte Cassino, and was given to Edinburgh Zoo in 1947. Less celebrated now, as his story hardly chimes with modern sensibilities, is a chimp called Philip. According to the zoo's founder Thomas Haining Gillespie, in his book published to mark its first 50 years, Philip came to Edinburgh in 1933 - an intelligent and sophisticated animal with a taste for cigarettes and alcohol which the zoo seems to have been glad to indulge. "Philip was not only an ardent but a very accomplished smoker and smoked with an "air,"" Gillespie wrote. He was quite catholic in his taste in liquor; beer he liked but it was not his favourite. He took a gin and bitters with appreciation, and whisky and lemonade was much in favour. His preferred tipple was port, quaffed from a wine glass. Despite such intemperance he managed to attract five mates; his last, Bunty, died of shock when, on the night of November 4, 1940, two bombs exploded in the park, ­courtesy of the Luftwaffe. These days, German aviators bring life, not death to the zoo; this coming Valentine's Day, a female koala, a mate for two males already in Edinburgh, is flying in on Lufthansa. Of course, zoos have plenty of decriers, to whom the whole concept of keeping animals in captivity, no matter how well-intentioned or how much their enclosure resembles natural habitat, is plain wrong. Animals, they argue, have a right to freedom, even if this means the freedom to die out. For these critics, a zoo reaching its centenary is a matter for condemnation not celebration. Yet this zoo is, it seems to me, a special place within the city - douceful and useful, an integral part of what makes Edinburgh Edinburgh. The DNA lab at the zoo also does brilliant, largely unsung conservation work, using the expertise in genetics of Royal Zoological Society of Scotland scientists to reintroduce species and battle international wildlife crime. Although pandas are the box-office draw, much of the most interesting work goes on behind the scenes. Take Ross Poulter and his snails. Poulter is a 34-year-old keeper who, in a former coal shed hidden away in the grounds of the zoo, has performed the closest thing science has to a miracle - bringing a species back from the brink of extinction. The dark, warm room measures around eight feet by seven. The walls are bare brick, the ceiling veiled in spider webs. Arranged on dusty wooden shelves are small glass tanks, sealed with clingfilm and resting against egg boxes. It couldn't look less like a laboratory. Yet these tanks are home to six extremely rare species of tiny Polynesian tree snails; two contain about 200 Partula simulans, which exist nowhere in the world except for this room. Three years ago, the zoo was given the last surviving simulans snail (this Abrahamic figure is by far the largest in its tank) which, luckily, had been fertilised - and from this Poulter has bred the rest. Every Friday he spends three trance-like hours cleaning the tanks while listening to The Archers and Gardener's Question Time, which he believes the snails enjoy. "A lot of the other keepers in here mock me, because they think this is my little hideaway," he says with a smile. But it's a good story, innit?