Why the humble tree squirrel is a master of deception and forest regeneration

Nature · Published 3 October 2026 Swipe more like this →

In short: Squirrels are not just frantic garden visitors; they are sophisticated hoarders who use complex social tactics to protect their winter supplies. While they are often viewed as pests, these arboreal rodents play a vital role in forest ecosystems, inadvertently planting the next generation of trees through their forgotten food caches.

Tree squirrels, members of the Sciuridae family, are highly adaptable, opportunistic omnivores. While they primarily consume tree seeds like acorns, hazelnuts, and walnuts, their diet is remarkably varied, including fungi, flowers, insects, and even bird eggs. Because they do not hibernate, they must survive the winter by caching food across wide areas. This strategy of scattering supplies rather than keeping a single larder helps mitigate the risk of cache pilferage, where other squirrels steal their hard-earned stores.

To protect these caches, grey squirrels have developed deceptive behaviors. When they sense competitors nearby, they may dig and cover empty holes to distract potential thieves. Despite these clever tactics, squirrels inevitably lose some of their buried food. This failure is a boon for the environment, as forgotten seeds often germinate, facilitating forest growth. Their homes, known as dreys, are intricate, football-sized structures woven from twigs and lined with soft materials like moss, typically situated at least six metres high in tree forks.

The relationship between squirrel species can be fraught. In the UK, the non-native grey squirrel—introduced as early as the 1870s—has significantly displaced the native Eurasian red squirrel. Grey squirrels are not only more numerous, with an estimated 2.5 million compared to 140,000 reds, but they also carry the squirrelpox virus, which is fatal to the native population. Conservation efforts are now focused on monitoring populations and relocating red squirrels to stable, protected habitats to prevent their further decline.

Beyond the forest, squirrels have adapted to human-altered environments, often becoming a nuisance in urban areas. Their constant need to gnaw—which prevents their teeth from overgrowing—can lead to property damage, including the destruction of electrical insulation and structural components. While homeowners often try to deter them with repellents or decoys, the squirrel's persistence and inquisitive nature make them difficult to manage, cementing their reputation as both fascinating ecological actors and challenging neighbors.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• Squirrels use deceptive tactics to trick rivals out of their winter food
• The forest's secret gardener hides in a tiny red coat
• Gray squirrels climb down trees head-first by reversing their hind feet
• Are ground squirrels just tree squirrels that decided to trade branches for deep tunnels?
• The fox squirrel is North America's largest tree squirrel, thriving from attics to forests.
• Meet the ancient, tail-wagging ancestor that paved the way for every modern frog
• Tree-kangaroos are the only macropods that traded the Australian bush for the canopy
• Why this reef fish uses a biological crossbow to survive in the ocean
• Why the red-eyed tree frog uses a startling flash of red to survive
• The sea robin is a bottom-dwelling fish that walks and tastes with its fins.
• Why the horned pheasant is neither a true pheasant nor a horned beast
• Why these bizarre, leathery turtles are masters of both land and underwater survival

More in Vertebrates · More in Nature · Latest · A–Z · All topics