What Spiders Do in Winter
WouterSpiders are cold-blooded creatures that have developed ways to keep their body temperature stable. During the winter months, some spider species enter a state of dormancy and wait for warmer days. They may build a web sac near the ground or in a pile of leaves.
Some species have the ability to warm their bodies by rubbing their feet over special glands on the mouths. They can also produce cryoprotectants in their blood, which prevent ice crystal formation and allow their tissues to remain unfrozen at below-freezing temperatures. Some spiders even produce glycerol, a natural antifreeze, to keep their bodies warm.
Some spiders build a wall of webbing to seal in cracks and gaps, while others leave their egg sacs intact. The sacs contain the young spiderlings, who will spend the winter in the sac. They are kept warm in their nest until the weather improves.
Some spiders are warmth hunters, which means they can eat prey that is still alive and thawing. This can be a useful trait in the coldest months of the year, but if they are not able to find food, they might go into diapause, which slows their movement. They might return to hunt on a warmer day or just sleep.
Whether they stay active in the winter is entirely up to the spider’s species. Some species of spiders, such as the widow and orb weavers, only live for one season. Other species, such as the eastern parson spider, will crawl beneath tree bark.
