The Norway Rat Rattus norvegicus has made it to the news recently as Alberta (which claim to be rat-free), watches a rat population explosion in Swift Current Saskatchewan, little over 100 kilometres from the Alberta border. This is an interesting story as it raises the profile of the much hated and much maligned rodent that some predict will survive long after humans have perished. While the Disney-Pixar movie Ratatouille may have persuaded some that rats are in fact interesting creatures, human repulsion to rats seems as strong as ever, based on the media coming out of western Canada.

Rats are rarely seen, but omnipresent in our settled landscapes. This is probably the most adaptable mammal on the planet which in many ways mirrors humans in our food preference, social structure and perhaps intelligence. The success of rats as a species is legend. They can reproduce at 3 months, they live in tight colonies of up to 200 or more individuals, females can produce litters of as many as 8 young as frequently as 8 times a years and young are independent after a month. They are opportunistic omnivores like us, eating everything, but with definite preferences for a good steak or filet. They are as tough as nails, can fit through tiny spaces as big as a loonie, yet hold their own against a domestic cat. Rats have non-stop growing incisors and very strong jaws. They are also largely nocturnal, one of the reasons why we don’t see them often. If you feed birds, particularly with platform feeders or ground feeders, chances are that you might have a rat or two visiting during the night.

Rats are considered such a scourge for two reasons – they cause large amounts of damage to food, grains, structures, buildings, electrical wiring, and other objects that we value. Rats have been know to cause floods by burrowing through dams, and fires by biting into matches or short-circuiting electrical wiring. Rats are always gnawing, always digging, and require large amounts of food daily, perhaps as much as 15 grams. Secondly they are carriers of several very serious diseases that can easily spread to humans such as bubonic plague, leptospirosis, typhus, spotted fever and tularaemia.

The Swift Current situation is certainly unnerving for the residents, who are looking both for an explanation and a solution with reports of some people even being bitten in their homes. Rat colonies are often underground in burrows, sewers or other dark and obscure spaces common in derelict buildings and factories. The cause of the rat explosion has been attributed to several factors that may have disturbed some colonies or led to a migration including a fire at the local landfill site, the demolition of a feed mill, drought and local construction.

This brings me to my final point. I predict that other Canadian cities and towns will experience rat issues in the next year as an indirect consequence of the federal stimulus package. Let me explain. The federal government is pouring money into infrastructure upgrading and replacing in municipalities. This means disturbing those aged sewer systems, canalizations and viaducts that harbor rat colonies. Demolition and construction activities will lead to more reports of rats on the streets, and more frenzy. Share your rat observations or stories with us at Nature Canada.