The only completely rat-free continent on Earth is Antarctica, where the extreme cold and lack of human habitation keeps them at bay. Otherwise, rats typically are found anywhere humans live -- except Alberta, Canada, which became a province in 1905. By the 1950s, rats had begun to make their presence known in the province. Fearing what rats could do to crops and buildings, the provincial government created a rat patrol, which has essentially wiped out all of Alberta's rats over the past 50 years. Pet rats are banned and residents are encouraged to call a hotline to report potential rat sightings. Occasionally, rats do find their way into the province, but aggressive pest control measures ensure that they don't survive long enough to become a breeding population.
Alberta vs. the rats:
- The province still maintains a dedicated pest control unit that patrols Alberta's borders, armed with shotguns and rat poison. The teams scour farms and ranches looking for infestations along the border with Saskatchewan. About 10 rats are found each year, but there are no permanent infestations.
- Alberta’s war on rats costs about $500,000 a year in Canadian dollars ($380,000 USD). A 2004 study estimated that rats could potentially cause as much as C$42 million ($32 million USD) in damage per year if not controlled.
- Alberta didn't have any rats before 1950, due to being surrounded on all sides by mountains, badlands, and forests. With western migration, rats eventually made their way to Alberta.