Squirrels are mammals and belong to the Order Rodentia and the Family Sciuridae. They are rodents like common rats. Squirrels are found in Europe, the Americas and Asia. The Flying squirrels also belong to this family. There are other types in Africa.
We have three species of squirrels in Sri Lanka, the small palm squirrels that you see in all rural and urban areas, the larger or giant squirrel that inhabits the forests, forest gardens and plantations and the flying squirrels, which are forest dwellers and which are active only at night.
Despite the popular impression that they are fruit and nut eaters, squirrels are actually omnivorous eating a wide variety of plant food, including nuts, seeds, fruits, fungi – for example, mushrooms – and green vegetation. They also eat insects and reportedly the eggs of small birds.
Squirrels, sometimes, are also pests because they chew on various edible and inedible objects. This habit helps keep the squirrel’s teeth sharp and also wears down the teeth. The teeth of many rodents grow continuously.
In temperate countries, during the winter, the trees and bushes all defoliate and as a result there is no food for the squirrels.
So during the summer they collect food, mainly nuts, and store them in hiding places to be eaten in the winter months. These nuts are hidden in many places and the squirrel knows exactly where to find them when the time comes. Fortunately for the squirrels in Sri Lanka there is food throughout the year. [WL]
Sri Lanka has three species of palm squirrels. They are the Flame-striped Jungle Squirrel (Funambulus layardi) called Wana Lena or Mookalan Lena in Sinhala and Karapu Anil in Tamil, the Palm Squirrel is (Funambulus palmarum) called Iri Lena in Sinhala and Sinna Anil in Tamil and the Dusky-striped Jungle Squirrel (Funambulus sublineatus) is called Pulutu Lena or Podi Lena in Sinhala and Sinna Anil in Tamil.
The Palm Squirrel is the most common species found in the island. The other two species are somewhat rare. There are four sub species of the Palm Squirrel.
These subspecies are found in different geographic locations in the country. One sub species is in the hill country, one in the wet zone and the other two in the dry zone – north and south.
Most times these sub species are difficult to identify unless captured. The palm squirrel is said to have got its name from its association with the Palmyrah Palm (Borassus flabelli).
All palm squirrels in Sri Lanka have three distinct stripes on their backs. The stripe in the middle is long and quite clearly seen. These squirrels have small ears, which are covered with soft fur.
They have bushy tails, which are as long or almost as long as their head and body. When they sit on their haunches to eat something, which is held between their paws, the tail is kept in the shape of an S.
The most rare of these species of palm squirrel is the Flame Squirrel, which has now been declared as endemic to this country.
It is a chocolate brown squirrel with three orange stripes and is found in the lowland and upland jungles. It is larger than the common palm squirrel and the Dusky-striped Jungle Squirrel,
The nests of the palm squirrels and the Dusky Striped Jungle Squirrel are untidy and globular. They are made of any material that these squirrels can find, dried grass, the soft bark of certain trees, wool, coir, string etc.
In fact anything that they can find. In urban areas it takes material from curtains etc. The nest is built in a leafy tree or the crown of a palm tree. In urban areas it builds its nests in the eaves of houses and other convenient places.
The entrance to the nest is from a side. Two or three young are born naked and blind. The Flame striped Squirrel, however, is said to build its nest in the hole in a tree trunk. The nest is lined with grass, dried leaves and fibrous material. Here too, two or three young are born.
Many Sri Lankan households, especially in the rural areas, have a squirrel as a pet. Some of them have the Giant species, but most have the smaller palm squirrel, since they are found almost everywhere. Squirrels can become very tame, be handled easily and will not go away if let out of its cage.
The Giant Squirrel (Ratufa macroura) is called Dandu Lena in Sinhala and Periya Anil in Tamil. Giant Squirrels are also known as Rock Squirrels.
This species is found in southern India as well, where it is called the Grizzled Squirrel. The grizzled giant squirrel’s common name comes from the gray to brown colouration highlighted with white at the top of the tail, giving it a grizzled appearance.
The rest of the body varies in colour geographically and may be brown, red, gray or black, but the fur on the underside is always lighter than the back.
This agile climber is adapted for life spent almost entirely in the trees, and has a very long tail for balance, broad hands for climbing and large claws for gripping branches. The ears are short and round. They have a tail that is about the same length of the body. They are very colorful mammals.
The colouration of the three sub species, found in Sri Lanka, varies. The Highland Giant Squirrel or Long-trailed Giant Squirrel (Ratufa macroura macroura) is called the Kalu Dandulena in Sinhala and Malai Anil in Tamil.
This squirrel has a black head and upper body. Its under parts are pale. Sexes alike but the female is sometimes a little bigger. They are found in the Central and Uva Hills, Nuwara Eliya, including the Horton Plains, and the Peak Wilderness.
The Lowland Giant Squirrel or Common Giant Squirrel (Ratufa macroura dandolena) is called Dandulena in Sinhala and Periya Anil in Tamil. This is the smallest of the Rock or giant squirrels found in Sri Lanka. It is also of a much lighter colour.
The Black and Yellow Giant Squirrel (Ratufa macroura melanochra) is called Kalu Dandulena in Sinhala and Malai Anil in Tamil. This squirrel is found in the forests and evergreen woodlands of the wet zone. However they have moved out of this range and mix about with the other sub species.
All giant squirrels are diurnal in that they are active by day and sleep at night. Even their daytime activities are confined to the early hours and later hours of the day when the sun is not hot. They are active in the early part till about 10.00 am and again from 4.00 pm till dusk.
During their resting period during the day and to sleep at night they use one of the many dreys or nests that they have built.
They also rest spread-eagled on the shady branch of a tree. Some villagers and estate labourers consider the flesh of these squirrels delicious and kill them for consumption. They are therefore vary of humans in these areas.
This giant squirrel is highly territorial and is very vocal upon encountering an intruder. It is usually found alone or occasionally in pairs. When frightened it will either flee, leaping up to six meters between trees, or will flatten itself against a branch, remaining motionless.
It is diurnal spending the day eating fruit, nuts, insects, bird eggs and the bark of some trees. They are also fond of very young coconuts as soon as they are formed and are the bane of coconut plantation owners.
The ears are short, round, and in the highland species, they are tufted. The hand is very broad, the inner paw is expanded for gripping, the feet are broad, and the claws are large and powerful. Females have three pairs of mammae.
These squirrels are arboreal in that they live in the trees and do not come to the ground. However they occasionally go to the ground only to chase another squirrel or to follow a female during the breeding season.
They are extremely agile in the trees, making leaps of six meters or more and progressing rapidly through the treetops. It is also capable of leaping from branch to branch. The leap is always slightly downwards to a lower branch.
When frightened it can flatten itself against the branch of a tree till it ascertains what the danger is. During the breeding season a large globular nest, which is also called a drey, smaller than the size of an eagle’s nest, is constructed in tree branches.
The nests in the jungle are hidden in dense foliage but in semi urban areas it is placed in the crown of a coconut or large mango tree, or some such large leafy tree. If during a drought the tree defoliates the nest is exposed and easily seen. The leaves and twigs that make up the nest are loosely intertwined.
They are placed about 50 feet above the ground.Records from tame squirrels that have been bred show that the gestation period is about a month. The giant squirrel gives birth to one or two young in a large nest high in the trees.
The young are looked after for several months before dispersing. Generally they raise one litter per year but it is believed by some that they may, in certain instances, raise more than one litter per year.
Sometimes a number of nests are constructed in the same tree by the same pair of squirrels. This is for them, not necessarily to breed, but to ‘hole up’ when there is danger or when the day gets too hot. Their enemies are monkeys, snakes, and raptors like kites, shikras and owls.
These squirrels do not sit upright with the tail arched over the back while feeding; instead, they balance themselves with their hind feet on a branch so that their hands are free to manipulate the food.
In this position the axis of the body is held at right angles to the support, with the head and forequarters on one side of the branch and the tail as a counterweight on the other side.
The very short, broad thumb is important in helping to hold food. Like all squirrels it can sit on its hind legs and hold its food, fruits and nuts, in its front paws much as we use our hands.
Giant squirrels are solitary or associate in pairs, and often they are wary and keep well hidden in dense forest vegetation.
These squirrels make a harsh trilling sound when alarmed. It is repeated by its mate or any other squirrels in the vicinity. This is a staccato sound. It also makes a low “churr” sound, which is indicative of pleasure or recognition.
The Flying Squirrels belong to the family Pteromyidae. Flying Squirrels are found in many parts of the world. The other mammals that fly, actually they glide, are the Flying Lemurs of Malaysia, the Flying Squirrels of America and the Flying Phalangers of Australia.
The phalanger is a marsupial. There are two species of flying squirrels in Sri Lanka. They are the Grey Flying Squirrel (Petaurista philippensis) called Maha Hambawa in Sinhala. Small Flying Squirrel (Petinomys fuscocapillus) called Kuda Hambawa in Sinhala.
The Large Flying Squirrel is more common than its smaller counterpart. They are dark silver gray in colour. Some species are dark brown. Both species are nocturnal. They have large beady eyes. When a light shines on their eyes, they reflect a reddish brown colour. They have very soft fur on their bodies.
Flying squirrels are forest dwellers and like the tall trees. They spend the daytime in the hollows of large trees and emerge only at night. They rarely come down to the ground. All other squirrels are diurnal meaning that they are active by day.
The large flying squirrel is fairly well distributed in the central regions of the island. They are common in Kandy, Matale and Teldeniya areas. They have been found in the Sabaragamuwa district and are not uncommon in the other upcountry areas. Recently a baby was found in the Uda Walawe National Park. They have also been seen in the Horton Plains National Park.
The appellation ‘flying’ is a misnomer because these squirrels cannot actually fly. They have fairly thick membranes, extending between the front and back legs on both sides, which they use as a parachute to glide down from tall trees to the branches of another tree lower down.
These membranes reach down to the toes of both fore and hind feet. The fore limbs and the neck are joined by small membranes, as are the hind limbs to the first two or three inches of the tail.
A fairly thick cartilage about six inches long on the edge of this membrane and starting from the front legs keeps the membrane from being limp. Without the cartilage, the flying squirrel would not be able to spread out the membrane and glide.
The flying squirrel is said to have a curious method of getting back to its nest hole, which is generally in the trunk of a tree. If, in its nocturnal forays, it has wandered downhill in search of food, the flying squirrel climbs up a tall tree and glides or ‘vol planes’ down to the base of a tree, which is higher up the hill. He then climbs up this tree and repeats this performance till he finally reaches the base of the tree in which his nest hole is.
They glide from in their nocturnal forays in search of food. To suddenly encounter a silent flying object, just above your head, in the forest at night is quite disconcerting. Since there is no flapping of wings, the glide is silent.
When the membrane is folded and the flying squirrel moves about the trees it seems to be clumsy because the membrane gets in the way. Its movements are not swift like that of a giant squirrel.
Flying Squirrels have rounded faces and rounded eyes. The face is not as long as that of a giant squirrel. It has small rounded ears, which stand up. The teeth are very sharp as I quickly found out from a tame giant flying squirrel that I had for about five years when I was on a tea plantation.
Flying squirrels subsist mainly on fruit with mango (mangfera indica) and Tamarind (Tamarindus indicus), raided from home gardens being a favourite. They also eat twigs, leaves, insects and larvae. They sit on their haunches, with their long tails in the shape of a large S and hold their fruit in their front paws when eating. Some times they drape themselves across the branch of a tree and eat their food again holding it in their front paws.
The nest is a hole in the trunk in a tall tree. It is lined with chips of bark and vegetative matter. Each year a single young is born. It is blind at birth and has a soft covering of down on its body.
The flying squirrel we had was very tame. It stayed in a box all day and in the night when it was let off would walk on the ground in a queer shambling gait. It would get on to the rafters in the kitchen where he had a good rapport with the staff who fed him well. He would spend most of his time moving about the rafters and occasionally going outside but, being tame, always came back.
Squirrels are an integral part of our biodiversity and since they have an important role to play and must be conserved. Their main role is the dispersal of the seeds of the trees throughout the forest so that these species of trees will continue to grow.