If decorating a tree is part of your December routine, you’re not alone. PEI’s Red Squirrels (Tamiasciurus hudsonicus) have been doing the same thing, albeit for a different reason.
There’s a part of my land in Central PEI I call “Squirrel Alley” because of all the activity. My daily walk there causes a loud serenade of angry chatters; once there’s snow, it looks like a Squirrel stampede passed through. I enjoy the annual autumn appearance of mushrooms and apples in the conifers of Squirrel Alley, where they’re left to dry over the course of a week or so before disappearing. Favourite branches get used and re-used, often with several things at once (Photo 1).
Red Squirrels are true omnivores, feeding on seeds, nuts, fruit, flowers, bark, insects, bird eggs, nestlings, small mammals, and miscellaneous dead things. While you may not think of Squirrels as fungivores, this part of their diet becomes especially obvious in fall as they collect and hang mushrooms to dry (Photo 2). As any gardener or forager knows, dried produce resists decay and stores well over the cold, dark months. Squirrels use this to their advantage, dehydrating fruit and fungi before storing them in a nearby tree cavity or underground cache. Placing mushrooms and apples in trees not only aids drying (Photo 3), but also keeps them out of reach of insects, slugs, or other animals that would devour them.
My Squirrels don’t seem to have any culinary preference when it comes to mushrooms and will cache top edibles as well as species we’d consider less tasty or even toxic. (I confess I sometimes trade with them, taking the occasional choice King Bolete [aka Porcini] and leaving a Scaber Stalk in its place). As an aside, it’s useful to remember that seeing an animal eat a plant or fungus doesn’t mean it’s safe for us to eat. Just think of some of the disgusting (to us) things dogs consume; mine will dine on long-dead mice or forage in the cats’ litter box if given half a chance. If you are going to trade with Squirrels, be sure to know your species!
Mushroom-caching is done for the Squirrels’ benefit, but there are advantages for the fungi as well. Spores from the elevated mushrooms can travel further, much like the difference in dropping a handful of dust from shoulder-level versus ground-level. Additionally, Squirrels help spread fungal spores in their scat.
If you’d like to see mushroom-drying Red Squirrels in action, check out this fantastic video by wildlife photographer Janet Pesaturo: https://fb.watch/oG--LMVJcb/ (I love her trail cam videos!). Janet is in Montana, but this Squirrel behaviour is also part of PEI untamed!