Alberta’s roughly 70-year experiment with rat eradication is the envy of the world. And what the province has achieved is a remarkable feat.
Alberta has prevented the establishment of breeding rat colonies through a strong commitment to keeping these rodent pests out. The Norway rat, known by its scientific name as Rattus norvegicus, is a wily foe. It is able to thrive in a variety of habitats, and is particularly good at surviving in urban landscapes and agricultural settings. Only a handful of other places on Earth have kept rats at bay — a few islands have eradicated invasive rats and Antarctica is safe, for now.
Genetic studies suggest that rats originated in Asia and spread over land to Europe. International sea shipping brought rats to the New World. They reached the west and east coasts of North America as stowaways on ships.
From these two main areas of introduction, they marched deliberately and effectively across the continent.
Alberta was able to take advantage of its geography for decades — the mountains in the west were an effective barrier, while few ports, sparse human population and a hostile climate in the north made their invasion from that direction unlikely.
They reached Alberta’s borders from the east in the 1950s and the provincial government decided to take a stand. They were ruthless in their efforts to keep Norway rats out and it worked.
The ongoing rat control program includes a rat hotline and email address for individuals to report rat sightings.
There are also active patrols and inspections in the rat control zone along the Alberta-Saskatchewan border. Sightings are investigated, and rats are swiftly dealt with.
Although some rats arrive over land, others get into the province by transportation on trucks and shipping containers. These are more likely to turn up in cities.
The importance of keeping Alberta rat-free cannot be understated. It is prudent to visit this topic now because we are facing increasingly tight provincial budgets combined with severe economic hardships and a global pandemic. There are many competing concerns at this time. But it would be short-sighted and disastrous if funding and resources for Alberta’s rat control program were cut.
Rats are responsible for billions of dollars in agricultural losses throughout the world. They are especially hard on stored grains, which there are plenty in Alberta.
In addition, rats can chew through many common building materials, resulting in infrastructure damage. More than one barn fire has been attributed to rats damaging electrical wiring, leading to fires.
In addition to crops and infrastructure, rats also carry a large number of pathogens. Many are zoonotic, those microbes that are hosted by animals that can pass to people. Plague is probably the most famous, but rats also carry the bacteria that causes leptospirosis, a serious liver infection, their own unique hantavirus and fecal bacterial.
My own research and that of other scientists have also established rats as hosts to pathogens of agricultural importance. For instance, rats in barns can pick up bacteria from the environment. When the opportunity strikes, they can then transmit those pathogens back into the herd or flock, either through direct contact, or through contamination of feed and the barn environment.
This is especially problematic for all-in, all-out production systems. Rats can host the pathogens between groups, rendering disinfection and quarantine measures less effective.
Elsewhere in the world, farmers have learned to live with rats, but due to a concerted effort, farmers and producers in Alberta haven’t had to.
As a province, Alberta faces many tough choices in the months and years to come. However, cuts to agriculture should not be directed at the Alberta rat control efforts.
It would be an incredible waste of 70 years to turn our backs on this remarkable program. The consequences for agriculture and Alberta’s cities would be devastating.
Dr. Jamie Rothenburger, DVM, MVetSc,PhD, DACVP, is a veterinarian who practices pathology and is an assistant professor at the University of Calgary’s Faculty of Veterinary Medicine. Twitter: @JRothenburger