Butaan are so shy they frequently remain in a tree for more than a week after being frightened. A large male we rescued from a trap hid in a tree for 22 days before coming down!* . Most lizards do not appear traumatised by being caught and released by scientists, and resume normal activity very quickly. But we think that butaan, especially older individuals, may permanently alter their activity areas after such an encounter. Because the animals are so shy, and highly vulnerable to human disturbance, we have had to develop a range of techniques that allow us to learn about them with the absolute minimum of interference.