Grey Squirrel - Nature's Acrobatic Tree Dweller
The grey squirrel is one of the most acrobatic of mammals.
It is hardly surprising that the grey squirrel makes its home in wooded areas since its primary food source, especially in autumn, are nuts, foliage and fruits that trees produce. Unfortunately, the damage the squirrel can do to the bark of trees, which it gnaws for the sweet, sappy tissue underneath, has led to its persecution by man.
Since its numerous introductions between 1877 and 1929 into the British Isles from North America, the grey squirrel has colonised most areas to the detriment of native red squirrels. However, the red squirrel survives on the Isle of Wight and Brownsea Island, Formby coast and pine forests of Northumberland and the Lake District, where there are no grey squirrels.
Versatile dweller
The grey squirrel has been known to cross water, marshland, bogs, and even swim across rivers outside its natural woodland habitat. It has adapted well to different environments, including urban areas. You will often find grey squirrels in town parks and gardens; wherever shelter of hedges, bushes or trees, it can make a home. The grey squirrel has become so familiar that it sometimes appears almost tame and takes food from the hand if approached carefully.
People living in towns are also well aware of the raids made on bird tables and hanging bird feeders. They are so agile and acrobatic that it is almost impossible to prevent them; however, many obstacles they encounter. They hang upside down, like a blue tit bird gripping a branch by their toes to get at nuts and seeds in bird feeders.
Grey Squirrel Watercolour and Pencil Artwork by Alison Langridge
Squirrel signs
Even if you know where to look for grey squirrels, you may not always see them immediately since they have a marvellous ability to camouflage themselves. However, an excellent place to look for them is in the treetops where they build their nests (drey).
Another sign to look for is the bark on the trunk or hardwood may also find split shells or husks or nuts fruit, cut tree shoots and buds, strips of scales or toothmarks on fungi. And listen for the characteristic scolding cry or 'chuk-ch chuk', which you may hear before seeing them.
Grey Squirrel Coat colouring
The grey squirrel's coat is short, sleek and brownish-grey on top of the body with a chestnut streak on the flanks and feet and often on the outer edges of the limbs. The tail hairs are thin with a white fringe. The winter coat is thicker, silver-grey on the top, with yellowish-brown fur on the head and along the flanks; the legs and feet are grey while the underneath of the body is white. The large, conspicuous bushy tail has dark grey fur with a white fringe.
There is little difference in colouring between the males and females, but the young usually have a greyer summer coat.
In some regions of Britain, you will notice some distinct variations in colour. Some grey squirrels have red-brown backs and can be confused with red squirrels. Occasionally, white albino grey squirrels with characteristic reddish eyes like all albinos. Black (or melanic) squirrels are the descendants of about a dozen black squirrels introduced into the Woburn Estate in Bedfordshire shortly after the arrival of the first grey squirrels.
Incessant nibbler
The grey squirrels are rodents and therefore gnaws at almost anything that grows on trees, including the tree itself— they like the sappy tissue found under tree bark, especially beech. Unfortunately, squirrels will sometimes eat birds' eggs and even young birds and insects. It will also eat farm crops such as swedes, wheat, barley and oat shoots, and the grain from these cereals at the 'milk' stage and when ripe.
All rodents have teeth that grow continually. They need wearing down before they become dangerous and possibly pierce the palate. Continuous gnawing trims the incisors down, and that is why you can always hear the sound of squirrels nibbling nuts and seeds.
Eating habits
The squirrel gnaws its food in the spot or carries it to a safe eating place somewhere high in the trees or fence post or tree stump, where it can watch its surroundings. The squirrel's eyes are large and set in the side of the head to give wide-angle vision. It also has an acute sense of smell, but its hearing is unexceptional,
In the late summer and autumn, the grey squirrel methodically sets about establishing its winter food store. It will later remember the rough location of the cache and the exact position. But, unfortunately, sometimes it forgets where the food is hidden, and here you will often see stored nuts sprouting.
Agile traveller
The grey squirrel is extraordinarily graceful and agile and can run up and down tree trunks, no matter how smooth the bark, with the greatest of ease. It will balance on the flimsiest twig and leap from branch to branch and tree to tree with complete confidence using its tail as a rudder. On the ground, the squirrel progresses in a series of short leaps or runs on an erratic course; its tail straight behind is held. It can reach speeds of up to 20 miles per hour. It frequently pauses to reconnoitre and sniffs the air, sitting upright on its hind feet with its tail flat along the ground and its ears erect. Surprisingly, the squirrel is an adept swimmer; it keeps its head and tail above the water, with the tail held up in its characteristic curve like a bushy sail.
Cycle of activity
The squirrel is active during the day, beginning before sunrise and ending well before sunset. It does not like extremes of temperature and will retreat to the cover of its drey in such cases. However, it cannot spend more than two or three days without food and often comes out of the drey to forage even in adverse weather.
Until recently, ecologists believed both grey and red squirrels hibernated during the winter or slept for long periods. Although you are unlikely to see squirrels in cold weather, they are about since their presence is given away, for example, by tracks in the snow.
Apart from games played by the young and the play, which forms part of the courtship ritual, male squirrels spend a great deal of time in high-spirited chases through the treetops, tail-biting and screaming; whether this is play or aggression is not known. Apart from the 'chuk-chuk-chuk' call, listen for a barking note, variations of purring noises and a sound (like the grasshopper song) made by males chasing females.
Grey Squirrel Watercolour and Pencil Artwork by Alison Langridge
Grey Squirrel Courtship
The grey squirrel has two mating seasons, the first occurring in May and the second in December. Courtship rituals involve display and chasing; several males sometimes pursue a female just before mating time, simultaneously engaging in running contests to see who gets the prize.
Preparing the drey
The squirrel's nest (drey) is rounded (about the size of a football), close-knit and made of leaves, twigs, bark, grass, and plant stems of ivy. Dreys are easily mistaken for a crow's nest, although the latter is an untidier affair.
After mating, the female becomes the dominant of the sexes, driving out the male from the nest tree and constructing the drey in which she will give birth. Alternatively, she may enlarge a previous drey or sometimes make her nest in the tree trunk hole, possibly taking over a woodpecker's old nest.
Treetop families
Once pregnant, the female squirrel drives out the male and prepares the drey for her young by giving it a soft lining of grass, dry leaves, moss and any other available soft materials.
In the drey, the female produces her young twice a year, six weeks after mating; this means litters appear in early-to-mid spring and mid-to-late summer. The young, usually three per litter, are born naked, blind and deaf; each weighs about 15g). They rely entirely on their mother's milk for seven weeks. After that, the mother introduces them to solid food but continues to suckle them for another three weeks or so. By this stage, the young start to learn the tightrope tricks that ensure survival in the treetops while also foraging and feeding themselves,
The female grey squirrel is a model mother and weans her blind and furless infants with great care, licking and cleaning each one individually. By the time the young squirrels are ten weeks old, they are scrabbling about outside the drey, and within another three weeks, they are out on their own. Their mother forces them out, or they wander away on their own accord as the mother squirrel must soon prepare for her next litter.
Young female squirrels can breed six or seven months after birth and usually do so by the time they are a year old. Grey squirrels can live as long as eight years, but this is an exceptional age. Most die in their first couple of years, and only a few live beyond six years.
Resisting Attack
The grey squirrel avoids most predators by living in trees, but it is still vulnerable to foxes, owls, hawks, wild and domestic cats, dogs and occasionally stoats. Birds and squirrels co-exist quite happily for the most part, although occasionally birds will mob a squirrel.
The greatest enemy is undoubtedly man; Squirrels cause extensive damage to valuable hardwood trees, and, since the 1920s, strenuous efforts have tried to curb the population. Recently, there has been discussion about exterminating them entirely by hunting, sterilising, and introducing predators such as pine-martins. However, pine-martins may cause as many problems as they prevent.
Dreys are destroyed, and grey squirrels are shot, trapped, poisoned and set upon by dogs.
Facts: Grey Squirrel (Sciurus carolinensis)
Size of adult 25-30cm overhead and body;
20-22cm along the tail.
Weighs about 500g, females slightly less
Breeding season Jan-July
Gestation period 42-45 days
Lifespan
No of young average 3, range 1-7 known to live 8-9 years,