Squirrels in the UK: what they are up to, when and why
Channel: Wild World
Date: 2022-06-19

The UK is home to two squirrel species: the Eurasian red squirrel (Sciurus vulgaris) and the grey squirrel (Sciurus carolinensis). 

The species you are more likely to see scampering through the trees or ransacking your bird feeders will depend on your location, though grey squirrels, which are not native to the UK, are now far more common in most areas.
What do squirrels eat?
Squirrels are omnivores. Most of the time they rely on plants, but their diet varies through the year depending on what is available each season. 

Both species eat tree seeds. Grey squirrels predominantly seek out high-calorie seeds such as acorns, beech nuts, hazelnuts, sweet chestnuts and walnuts. Red squirrels eat these seeds too, but they will also feast on smaller seeds from conifer cones. 

Squirrels will also dine on flowers, fungi, shoots and some plant bulbs, as well as sometimes turning to insects, such as caterpillars, bird eggs and even nestlings. 

They are opportunistic feeders. So, if you provide food for birds in your garden, you may also see these supplies diminished by squirrels taking advantage of an easy meal. 

Why do squirrels bury food?
Winter is tough for squirrels, with fresh food in short supply. To get themselves through the lean times, they hoard food, storing it underground in shallow holes. Red squirrels are also know to cache fungi in tree crevices. They will return to these supplies throughout the cold months. 

Squirrels don't use a single central larder. Instead, they hide their foraged food across a wide area. It's thought this reduces the impact of cache pilferage on the forager's winter supplies. This is where another squirrel takes food it didn't collect itself. While they will inevitably still lose some food in this way, they might also reciprocate by taking food that other squirrels have collected. 

Squirrels dig small holes in the ground that they will usually bury food in. These stores help them survive winter food shortages. © Shredda via Wikimedia Commons (CC BY 3.0)
Grey squirrels have been known to use deceptive tactics to protect their supplies. When other squirrels are around, they will dig and cover some cache sites without actually burying any food in them. It's thought that, while they rely on their noses to find food when they need it, squirrels also use visual cues. Deceptive caching may serve as a distraction, preventing carefully foraged food from being stolen immediately by other opportunistic squirrels. 

When winter's fresh food shortages arrive, squirrels will locate and use up most of their stored supplies, but they won't find them all again. This inadvertently benefits the next generation of squirrels, as these buried seeds stand a chance of growing into new trees that produce new sources of food.