Rat control in Alberta
Since the mid-20th century, the Canadian province of Alberta has maintained an essentially rat-free status through a rigorous rat control program. Alberta is bounded by the Rocky Mountains to the west, boreal forest to the north, and with long treeless prairie and semi-arid regions to the south. The most feasible point of rat entry has historically been its eastern border with the neighboring province of Saskatchewan. Norway rats are invasive rodents known for spreading disease and damaging crops and property. They had been advancing across the Prairies and reached Alberta's eastern border in 1950. Faced with the risk of plague and agricultural losses, the provincial government immediately declared rats an agricultural pest and waged a war on rats.