The Most Poisonous Spiders in Ontario

No pest elicits the same kind of fear and revulsion that spiders do. With their spindly legs, multitude of eyes, and venomous bite, they’re nature’s favourite little nightmare machines. But luckily, we Canadians don’t really have to worry the truly dangerous varieties of spiders…right?

Think again.

While exceedingly rare, Black Widow Spiders have been discovered in Ontario, as far north as Newmarket and Mississauga. With a terrifying appearance and a bite 15 times more poisonous that a rattlesnake’s, the fact is black widows make arachnophobia seem less like a phobia and more like a legitimate fear.

However, if you arm yourself with relevant Black Widow spider facts, you won’t have to worry about black widow spider bite symptoms in Ontario ever again.

Seriously? Are There Black Widows in Ontario?

Would we lie to you?

Black Widows are more than just the most poisonous spiders in Ontario, they’re the second most venomous spider in the world, just behind the Brazilian Wandering Spider. However, whereas Brazilian Wandering Spiders are located solely in South America, Black Widow species can be found across the United States and Southern Canada, in British Colombia, as well as Southern Ontario.

Of course, everyone’s favourite Black Widow Spider fun fact is that the females eat the males after mating, but did you know that black widow hatchlings’ have amber and white colouration until they mature into that slick black carapace with sinister red markings we’ve all seen in our worse night terrors.

However, despite their sinister appearance and vicious neurotoxin, Black Widows are actually quite docile and will not attack humans unless provoked, even going so far as playing dead. And even if you do have the poor fortune of getting bit by one, black widow bites have a less than 1% mortality rate.

Even for the second most venomous spider in the world, spider mandibles are made for neutralizing very small prey, not fully-grown humans. While black widow spider bites have a variety of deeply unpleasant symptoms, a healthy adult should be able to recover in a matter of days. Of course, if such an unlikely event should occur, you should still seek immediate medical attention and call Terminix Canada for expert spider control and removal.


Worried about whether there are Black Widows in Ontario homes like yours this Halloween? Don’t hesitate to call Terminix Canada for a free consultation. We’re the GTA’s foremost provider of spider control and spider removal and we’d be happy to assuage your spider fears. Call us today.