Experts say the city’s rat problem remains an environmental management challenge that artificial intelligence can help monitor, but not solve on its own. HONG KONG: Rats have long thrived in Hong Kong's crowded streets, parks and back alleys despite years of pest control efforts and complaints about widespread infestations. "I used to live in one area and there were a lot of rats – and then when I moved to a new place, (there were) still a lot of rats. They are huge," said a Hong Kong resident