There are not as many things in this world as adorable as a squirrel. These little creatures are so full of energy and personality that it’s hard not to love them. Like most people, you have probably spent some time watching these busy animals go about their day. But do you know if squirrels are nocturnal or diurnal? It turns out the answer isn’t black and white. Although squirrels are primarily diurnal, several species are crepuscular or nocturnal. This article explains their sleep behavior and helps better understand these cute little creatures.
Sleeping Behavior of Diurnal Squirrels
Diurnal animals are primarily active during the day. Many factors can influence an animal’s sleeping patterns, including its natural predators and prey. The availability of food and water affects the sleeping behavior of diurnal animals. Diurnal animals are more likely to be active when plenty of food is available.
As it turns out, most squirrels are diurnal animals. In the wild, they are most active in the morning and afternoon, spending the rest of the time resting or sleeping in their nests. During the winter, when food is scarce, squirrels may change their sleeping patterns and become more nocturnal to find enough to eat. However, squirrels are generally diurnal creatures most active during the day.
The Diurnal Red Squirrel
The diurnal red squirrel (Sciurus vulgaris) is a type of squirrel that is active during the day as it looks for seeds, nuts, and berries. It is native to North America. However, people have introduced this species to other parts of the world, including South America, Africa, Australia, and New Zealand. It is common to see the red squirrel with its reddish-brown fur and white underbelly scurrying around during the day. Its daily habits are a protective avoidance of its natural predators, such as owls and foxes.
Sleeping Behavior of Nocturnal Squirrels
When most people hear the word “nocturnal,” they think of creatures of the night, like bats or owls. But the term refers to any animal that is active during the night and sleeps during the day. This phenomenon includes several species of squirrels. You can see them scurrying or gliding (flying squirrels) about in the early morning or late evening hours.
There are several reasons why squirrels are nocturnal. As with crepuscular and diurnal squirrels, it helps them avoid their natural predators during their preferred cycle. Another is more opportunities to find food at night when many other animals are asleep. Finally, nocturnal squirrels use their night activity to avoid human contact, which threatens their safety.
The Nocturnal Flying Squirrel
The nocturnal flying squirrel is a small mammal proficient at gliding through the air. There are over 64 species of this mammal, with many possessing large eyes that are well-suited for night vision. Some of these flying squirrels have pale furry coats, helping them to blend in with their nighttime surroundings.
The flying squirrel sleeps during the day, curled in a tight ball in a nest of leaves high up in a tree. When night falls, the flying squirrel becomes active, searching for food using its long tail and limb flaps to glide from tree to tree. The flying squirrel feeds on nuts, seeds, and insects, which it stores in its cheeks before returning to its nest to sleep through the day.
Sleeping Behavior of Crepuscular Squirrels
The term crepuscular stems from the Latin word crepusculum, meaning twilight. Crepuscular refers to the time of day when these types of squirrels are most active, typically in the early morning, late afternoon, or early evening.
While many squirrels are diurnal, sleeping primarily at night, crepuscular squirrels sleep most of the day. They are only up and about for a few hours, around dawn and dusk. This type of activity pattern is known as cathemeral, as activity occurs sporadically throughout the day and night.
There are several reasons why crepuscular squirrels may have evolved this behavior. For one, it allows them to avoid predators during the daytime or nighttime. Additionally, it helps them to avoid competition with other squirrel species that occupy different niches.
Finally, it enables them to take advantage of resources that may be more abundant during certain times, such as food or shelter. Regardless of its reasons, the crepuscular lifestyle of these creatures is an intriguing adaptation that helps them survive in various environments.
The Crepuscular Gray Squirrel
The crepuscular gray squirrel sleeps for about 13 hours per day in 2 to 3-hour intervals. It typically sleeps in a nest made of leaves and twigs during the day and becomes more active in the twilight hours. This sleep pattern is an adaptation to avoid predators, as well as to conserve energy. The crepuscular gray squirrel is an integral part of the ecosystem. It plays a role in dispersing tree seeds and controlling insect populations.
Where Do Squirrels Sleep?
Squirrels sleep in a variety of habitats. These animals are agile creatures adept at scrambling up trees and leaping from branch to branch. Many squirrels build nests in the forks of trees. The nests consist of twigs and leaves with a soft inner lining of moss. Some squirrels rest in their nests during their sleep cycle, but others will find a cavity in a tree where they feel safe. Ground squirrels typically build their burrows underground to stay safe and warm.
Squirrel Eyes and Vision
Squirrels come in various shapes and sizes and have diverse sleeping patterns depending on the species. Other distinguishing features include each species having unique eyes and vision adaptations that help navigate their environments. For example, diurnal squirrels have smaller eyes and cells in their eyes. This eye structure lets them absorb more light, giving them good daytime vision.
Nocturnal squirrels have larger eyes with excellent night vision. Their eyes have adapted because of the biological differences in the retina that enhance what they can see at night. Still, they have poorer eyesight during daytime hours.
Crepuscular squirrels have average-sized eyes that allow them to see well in both low-light and bright-light conditions. Interestingly, while all types of squirrels have good vision, each group is adapted to its particular environment and needs.
Hibernation in Ground Squirrels
Ground squirrels (Spermophilus lateralis) are the only squirrels who truly hibernate during the winter months. Some squirrel species slow down their activity level and spend more time in their nests. However, ground squirrels go into a deep sleep, lowering their body temperature and heart rate.
They can even enter a state of torpor, where their body temperature drops so low that they are barely alive. This way, they can survive on stored fat until spring arrives. Ground squirrels are the only type of squirrel that undergoes true hibernation.
Hibernation in Most Squirrels
According to scientists, most squirrels do not hibernate in the traditional sense of the word. Instead, they gather food for the winter during the summer months, then enter a phase of less activity, snuggled up in their nests. This dormancy state is where they decrease their body temperature and metabolism, helping them survive the cold months. Squirrels have adapted to the changing seasons in a way that allows them to thrive.
Nocturnal vs. Diurnal: What’s The Difference?
Navigate to Nocturnal vs. Diurnal: What’s The Difference? for further information about the nocturnal and diurnal phenomenon in various living creatures.
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