"The number of rats in Canada's biggest cities is skyrocketing, spurred on by this summer's dry, warm weather." 'They have invaded'Vancouver was among big cities that were dealing with an increase in rat populations during the summer of 2001. A trend of growing rat populations in some of Canada's big cities caught The National's eye in August 2001. (The National/CBC Archives)The rat population was also on the rise in the big cities of Toronto and in Montreal. (The National/CBC Archives)Leavey said the warm weather, preceded by a mild winter, made for perfect weather for families of rats.

Source: CBC News August 23, 2020 12:22 UTC