Three new cotton-tops born at Perth Zoo THEY are barely a few centimetres tall but they are already showing signs of being feisty little monkeys. Three cotton-top tamarins were recently born at Perth Zoo - one in December and two in January - bringing the zoo's total population to 23. Zoo keeper Katie Saunders said while the Colombian animals did not have names yet, they were already making an impact on the primate enclosure. Ms Saunders said the youngsters were quite confident and at the age of two months would start to climb off the adults' backs and try to steal food that others had collected. "They are feisty when they are young," she said. Cotton-top tamarins are critically endangered due to habitat destruction and the illegal pet trade. More than 5000 of the 6000 primates left in the world were in captivity, Ms Saunders said. The animals, known for their distinctive white mane that tapers to a mohawk, are omnivores and eat insects, fruit, spiders, sap, leaves, nectar, birds' eggs, lizards and small tree frogs. To stay safe in the wild, cotton-top tamarins form large groups and at Perth Zoo the biggest group has eight members, Ms Saunders said. The animals are hunted by small native cats, birds of prey and large snakes. "The key to their survival is banding together in the wild," Ms Saunders said. They alert each other by chatting. Ms Saunders said that survival instinct still existed in the enclosure so visitors to the zoo could hear the primates communicating with each other.