Today’s post comes from Pilar Manorome, a natural heritage education specialist from Rondeau Provincial Park.

While you’re cuddled up on the couch with your favourite book and a big cup of hot chocolate, have you ever wondered where our eight-legged friends spend the cold winter months? Well, I’ve got the answers to your winter-time ponderings.
Spiders are members of the phylum arthropoda – animals that have jointed appendages, exoskeletons, and are ectothermic (“cold-blooded”). As such, they’ve adapted to dealing with cold weather in a variety of ways. It all depends on the species.
Some spiders are like Charlotte
Most of our North American spiders live for just one season as an adult, and their sole purpose is to produce eggs – often time this occurs in the fall. The young spiderlings will either overwinter in their protective egg-sacs made by the silk of their mother, or in the insulating leaf litter during one of their instar stages (like spider adolescence), before becoming adults in the spring. Some species will overwinter as an adult and produce eggs over the winter, or in the spring, but this seems to be less common.

Spiders have a sort of “antifreeze” in their bodies that allow them to remain outside throughout freezing temperatures (typically down to -5°C, some can even survive colder). We are less likely to see spiders outside throughout most of the winter as these spiders (and spiderlings) will stay relatively inactive in their insulated shelters – but on those warmer winter days, a few species of spiders have been found on the surface of the snow.
Others are house- and cave-dwellers
Some species of spiders depend on more climate-controlled environments like caves and houses. These spiders often live longer, and have the ability to mate and produce eggs at any point in the year. In this case, they just continue on with normal life regardless of the temperature outdoors.
Debunking the myth: Spiders come inside for the winter
For the most part, an outdoor-dwelling spider will remain outdoors, as the changes in environmental conditions are an important part of their lifecycle. An indoor-dwelling spider will only survive in their climate-controlled environment. Most spiders do not need to “migrate” into our warm and toasty houses to beat the cold as they have figured out a way to do it on their own!