B.C. is banning the use of rat-killing rodenticides over concerns the poison is inadvertently killing owls, among other wildlife.
The ban will last 18 months and follows a series of prohibitions at the municipal level in B.C., including in North Vancouver.
The provincial order took effect Wednesday, prohibiting second-generation anticoagulant rodenticides (SGARS) specifically, which the province said is particularly strong and risks the secondary poisoning of animals who consume poisoned rodents.
"It's a long time coming," said Elise Roberts, co-founder of Owl Watch B.C. Roberts is among those who had been lobbying for a municipal ban in North Vancouver, which was passed by the district last year.
"Rodenticides are prolific everywhere in our communities," she told CBC News. "You find those little black boxes everywhere. It looks like they're being used as a first resort rather than a last resort, and it really is having an impact on owls."
During the 18 months, the province says it will conduct a scientific review of rodenticides and promote alternatives.
"We share the concerns of many British Columbians that rodenticide use is harming, and too often killing, birds, pets and other wildlife," said George Heyman, the minister of environment and climate change strategy, in a statement.
Exemptions to the temporary ban include when use supports agricultural production and food safety. Health services, such as hospitals, food processing and storage facilities, restaurants and grocery stores, are also exempt.
Rat poison has been widely criticized for how it moves through the food chain after it's ingested by a rat. Trace amounts are found in local wildlife and can be harmful to predators like owls.
A 2009 study on 164 owls in Western Canada found that 70 per cent had residues of at least one rodenticide in their livers. Researchers found that nearly half of those owls had multiple rodenticides in their system.
Rat poison has also been found in higher-order predators like weasels and coyotes, as well as scavenger species like birds and squirrels.
Opponents say the use of rat poison contradicts Canada's guidelines for hazardous materials.
The B.C. SPCA urges people to rodent-proof their homes instead of relying on rat poison.