Why Alberta has no rats

What "rat-free" actually means

It does not mean rats never turn up. The province's own wording is that there is no resident population and none is permitted to establish itself. Small infestations do occur, and when one is found it is isolated and eradicated.

The animal in question is the Norway rat. It is not native to North America — it arrived on the east coast around 1775 and spread west as the continent was settled, farms were built closer together, and cultivated land came to dominate the landscape. It is unusually dependent on people: it cannot survive in natural areas here and cannot overwinter in cultivated fields in Canada. It needs human buildings, which is precisely what makes it possible to keep out.

The rats arrived in 1950, and the law was already waiting

Rats reached Saskatchewan in the 1920s and pushed northwest at roughly 24 kilometres a year. They were first reported on Alberta's eastern border in 1950, found on a farm near Alsask that summer.

The discovery was incidental. The field crews who made it were from the Alberta Department of Health and were studying sylvatic plague in Richardson's ground squirrels. The province's first concern was not crop damage but the possibility that rats would spread plague, and responsibility for rat control moved from Health to Agriculture that year.

The useful accident is that the legislation predated the rats by eight years. The Agricultural Pests Act of 1942 already let the Minister designate any animal likely to destroy crops or livestock as a pest, and already required every person and every municipality to destroy designated pests and prevent them establishing. When rats were declared a pest in 1950 the machinery was in place, and an amendment that year required every municipality to appoint a pest control inspector.

The zone

The control zone was conceived by William Lobay, a crop protection supervisor, who organised and ran the programme from 1950 to 1953. It runs the length of the Saskatchewan border — about 600 kilometres from Cold Lake in the north to the Montana boundary in the south — and is roughly 29 kilometres wide.

Seven rural municipalities inside that strip carry most of the work, supported by provincial funding and supplies. Farmers, counties, pest control officers and provincial staff all take part. The early programme leaned heavily on public education, because most Albertans had never seen a rat and did not know what one looked like.

What this means if you live here

It is illegal to keep a pet rat in Alberta. That sounds like an oddity until you consider that a single released or escaped pair is exactly how a resident population starts.

If you think you have seen a rat, the province asks you to photograph it if it is safe to do so, note the location, and report it. Sightings from the public are part of how the programme works — most of what gets reported turns out to be a muskrat, a pocket gopher or a bushy-tailed woodrat, and the province publishes guidance on telling them apart.