North Campus, on the Kamla Nehru Ridge, is home to large numbers of Rhesus Macaques or ordinary monkeys. There have been several cases of monkey bites as well monkeys jumping into libraries and tearing books and documents. Fed up of the menace, many Delhi University (DU) colleges have hired langurs to keep them at bay. The langurs are accompanied by their trainers. St Stephen’s pays their langur Rs 6,000, Hans Raj college pays Rs 4,500. According to DU norms, all contractual employees at the post of a guard are paid Rs 3,000. “We pay Rs 4,500 per month to the langur and his trainer. He comes in the morning when college opens and stays till evening,” says S R Arora, principal of Hans Raj College.