The days are shortening, there’s a chill in the air, and everywhere you look the trees are starting to turn. It’s autumn.
There is a huge amount of squirrel activity over these next few months, and for many squirrels it’s make or break. Autumn is the point in year when there is the most natural food available to squirrels. As trees set their seed in late summer squirrels eagerly anticipate the feast to come. They often start eating and gathering various fruits and seeds whilst they are still ripening. They will be keen to eat their fill as soon as they can, but also to begin hoarding seeds in their stores (called ‘caches’) for the winter period.
Squirrels are scatter hoarders, meaning they move seeds around and bury them throughout their home range.
Key foods they will be seeking out are beech, hazel, and oak, all of which will be producing mature seeds right now. The amount varies from year-to-year, with some years pretty lean and some years producing vast amounts of food.
Summer is a tough time for squirrels, with little natural food and the stresses and strains of the breeding season taking a toll. Some female squirrels will have had two litters and will be in poor condition. They will need all the food they can get to see them through winter. Studies have shown that females that spend more time storing and retrieving food enjoy far better winter survival. Likewise the young squirrels called ‘kittens’ will be dispersing around now, many of these won’t make it, but the odd one will find a suitable wood and set up home.
As winter approaches, grey squirrels begin to add to their winter nests or dreys. The female squirrel builds a summer drey to house her youngsters and this is usually a rough ball of twigs and leaves lined with straw moss or feathers often in a tree-hollow or sometimes in a fork in the trunk or between high branches.
But in autumn, the squirrels anticipate the coming winter by boosting the insulation on their dreys in case they need to sleep out a cold snap. They don’t hibernate here in the British Isles, but will take to their dreys for few days at a time to ride out freezing, windy or damp conditions.
When they emerge, they search for the nuts and other food that they have buried as insurance against severe weather. In winter, some grey squirrels can even produce a litter of youngsters, whose survival is boosted by their parents ability to find food. Raiding of bird-tables is a regular habit and no doubt increases their chances of survival at this precarious time when their favourite large seeds are in short supply. I know they aren’t native and wouldn’t it be amazing to see lots of our native red squirrels everywhere but I can’t help smiling when I see these busy little creatures around.
Be warned not all grey squirrels build dreys in trees. Many will winter around old buildings or in roof-spaces where they can be a nuisance, gnawing electrical cables.