Eastern gray squirrel

The gray squirrel has gray fur. It often has brown spots.

Some squirrels are even black. These black squirrels stay warm in the cold.

Baby squirrels are born pink. They have no hair. They are also blind when they are born. They grow hair as they get older.

These squirrels are very smart. They hide food in many spots. They use landmarks to find it later.

They can turn their feet. This lets them run down trees head-first. They also build nests in trees. These nests are made of twigs and leaves.

Gray squirrels are found in many lands. They are very good at living in new places.

The eastern gray squirrel lives in North America.

It is native to the eastern and midwestern United States. It also lives in parts of Canada. These squirrels have gray fur with brown spots.

Some squirrels are almost entirely black. This is called melanism. Black squirrels stay warmer in the cold.

Baby squirrels are called kits. They are born pink, hairless, and blind.

Their eyes open after a few weeks. They grow into adults by nine months.

These squirrels are very smart. They are scatter-hoarders. This means they hide food in many small spots. They make thousands of these caches each season. They use landmarks to find their food later. Sometimes they even trick other animals. They may pretend to hide food to fool thieves.

Gray squirrels can run down trees head-first. They do this by turning their hind feet. This lets their claws grip the bark. They also build nests called dreys. These nests are made of twigs and leaves.

The eastern gray squirrel is a busy animal found in North America.

It is native to the eastern and midwestern United States. These squirrels also live in southern parts of Canada. They are very important for helping forests grow again. This happens because they hide seeds in the ground. In some places, like Europe, they are called an invasive species. This means they were brought there by people and can crowd out local animals.

These squirrels have a very clever way of finding food. They are scatter-hoarders, which means they hide food in many small spots. Each squirrel might make thousands of these little caches in one season. They use landmarks like trees or rocks to remember where they hid things. They even use their sense of smell to find their snacks. Sometimes, they try to trick other animals. A squirrel might pretend to bury food if it feels watched. This helps keep their real food safe from thieves.

Scientists have studied these squirrels for a long time. Their scientific name is Sciurus carolinensis. The name Sciurus comes from Greek words meaning "shadow tail." This describes a squirrel sitting in the shadow of its own tail. The name carolinensis refers to the Carolinas. This is where the species was first recorded.

There are many interesting facts about how they look and grow. Most have gray fur with brown streaks and a white underside. Some squirrels are almost entirely black due to a mutation called melanism. These black squirrels can stay warmer in the cold.

Baby squirrels are called kits, kittens, or pups. They are born pink, hairless, and blind. Their eyes open after about three to six weeks. An adult squirrel can reach its full weight by nine months old.

Gray squirrels are amazing climbers. They are one of the few mammals that can run down a tree head-first. They do this by rotating their hind feet. This lets their claws grip the bark as they go down. They also build cozy nests called dreys. These nests are made of twigs and leaves.

They often add moss or feathers to keep the nest warm. Squirrels can even share a drey to stay warm during winter.

The eastern gray squirrel, known scientifically as *Sciurus carolinensis*, is a highly adaptable tree squirrel.

It is a vital part of its native ecosystem in eastern North America. These squirrels act as natural forest regenerators. They do this by hiding seeds that eventually grow into new trees. However, when moved to new areas, they can become problematic. In Europe, they are classified as an invasive species. This means they can crowd out local wildlife. Because of this, the European Union prohibits their import or intentional release.

This species is native to the eastern and midwestern United States. It also lives in southern parts of Canada, such as Ontario and Quebec. In the mid-1800s, their numbers in the midwest were described as astonishing. Later, human activities like deforestation caused their numbers to drop significantly. By 1900, they were almost gone from Illinois. Today, their range extends from New Brunswick down to Florida and East Texas. They sometimes overlap with the fox squirrel, *Sciurus niger*. You can tell them apart because gray squirrels have white undersides.

The eastern gray squirrel has several unique physical traits. Most have gray fur with brown streaks and a bushy tail. Some squirrels possess a melanistic form, which means they are almost entirely black. This color comes from a mutation of the MC1R gene.

This dark fur helps them survive in cold climates. When exposed to -10 °C, black squirrels show an 18% reduction in heat loss. They also show an 11% increase in non-shivering thermogenesis, which is a way to create body heat. Adult squirrels vary in weight and size, but they do not show sexual dimorphism. This means males and females look very similar.

Growth and development follow a specific sequence for these animals. Newborns are called kits, kittens, or pups. They are born pink, hairless, and blind. Their skin begins to darken about 7 to 10 days after birth. Their lower incisors erupt between 19 and 21 days. Their eyes usually open between 21 and 42 days. By week 6, their cheek teeth begin to emerge. Weaning typically finishes by week 10. A squirrel will reach its full adult body mass by 8 to 9 months of age.

Squirrels use complex behaviors to survive and find food. They are scatter-hoarders, meaning they hide food in many small caches. An individual squirrel might make several thousand caches in one season. They use landmarks and a strong sense of smell to find them. They even use deceptive behaviors to trick rivals. A squirrel might pretend to bury an object while actually hiding it in its mouth. This suggests they may possess a "theory of mind," which is a type of advanced thinking.

Their physical abilities allow them to navigate trees with ease. They are among the few mammals that can descend a tree head-first. They achieve this by rotating their hind feet. This allows their claws to grip the bark as they move downward. For shelter, they build nests called dreys.

These spherical nests are made of twigs and leaves. They often add moss, feathers, or grass for insulation. Squirrels may also live in tree hollows or even in the walls of houses.

Finally, it is important to understand the health risks and history of the species. The fossil record shows they have existed in North America at least 18 times during the Pleistocene epoch. They can also carry various diseases and parasites. Ticks carried by squirrels can spread Lyme disease or Rocky Mountain spotted fever. They can also suffer from illnesses like squirrelpox or fibromatosis, which causes large skin tumors. While they are essential to North American forests, their presence in places like Vancouver Island or Britain can threaten native species like the American red squirrel or the Eurasian red squirrel.