Asian Elephant

Distribution & Habitat

Asian Elephants live in the forests and grasslands of India, Sri Lanka, Myanmar (Burma), Indonesia, Bhutan, Thailand, Cambodia, Vietnam, Laos, Malaysia, Nepal, Bangladesh and southern China. Across all these regions their natural habitat has been greatly reduced resulting in massive declines of wild populations. In Thailand, a country synonymous with the Asian Elephant, the wild elephant population now may only be 1,500. At the current rate of decline they could be extinct in the wild within 20 years.

Lifespan

On average elephants can live up to 50 - 70 years of age. However, due to poaching and the on-going clearance of forests and natural habitats which result in human-elephant conflict over resources many wild elephants are no longer reaching this age span. The oldest Asian elephant recorded in Australia was 'Jesse' which lived at Taronga Zoo up until 1939 and was 69 years old.

Behaviour

Female and young elephants live in cohesive family groups called herds. Many of the adult females are related and the herd is led by a 'matriarch', usually the oldest or most experienced in the group. The matriarch sets the pace and direction of the herd's activities and these movements usually depend on food and water availability. Male offspring either leave or are driven from these family herds as they begin to mature sexually and become increasingly disruptive. Young males sometimes band together in bachelor groups spending many years sparring to determine their dominance in the bull hierarchy. Once mature, male elephants will usually only socialise with herds when the females are reproductively cycling.

Intelligence/ Communication

Elephants are extremely intelligent and social animals. The brain of an adult elephant weighs 4.5 -5.5 kg. Elephants have a complex repertoire of communication that includes touching, body posturing and vocalising. Many of these sounds are below the range of human hearing. This is called infrasound and can travel for over a kilometre.

Size and Weight

Males can exceed 5,000kg in weight and can reach over three metres at the shoulder. Females reach weights up to 4000kg and nearly three metres in height at the shoulder.

Teeth

Elephants develop six sets of molar teeth throughout their lifetime. They have large molar teeth on either side of the upper and lower jaw. These teeth have ridges which are slightly different in shape and appearance between African and Asian Elephants. As elephants’ teeth become older, a new set develops from behind and move forward, similar to a conveyor belt system. These teeth are grown and lost at regular intervals during an elephant's lifetime and are a good indicator of an elephants age. Once the last set of teeth is worn away, the elephant cannot chew properly and soon passes away from malnutrition. While each individual is different this usually occurs over 60 years of age.

Tusks

Male Asian Elephants have tusks. Tusks are modified incisor teeth and are made of dentine (ivory). 50% of Asian Elephant females grow tushes which are much shorter than tusks and in some cases may not be seen under the trunk. Other females do not develop tushes at all.

The longest recorded tusk of an Asian Elephant bull was 302cm long and weighed 39kg.

Heart/Respiration

The heart of an elephant is huge, weighing 12 - 21kg. In relative terms however, it only weighs 0.5% of the elephants body weight which is normal for large mammals (human hearts are approx 0.4% of overall body weight). The average heart rate is 25 - 35bpm but rises if an elephant gets excited. An elephant’s respiration rate is only 4 - 6 breaths per minute but can rise to 15 if they get excited. While elephants can breathe through their mouth the majority of air is taken through the trunk.

Skin

The skin on an elephant’s body varies in thickness from a few millimetres around the ears to almost 3cm on other parts of their body. Despite its thickness, the skin is sensitive with sparse hair and bristles all over the body. Baby elephants are very hairy when born and this hair gets sparser as they get older. Many Asian Elephants also lose pigment in their skin, most noticeably on the trunk and ears. This results in large patches of pinkish colouration in these areas.

Food/Digestion

Elephants are generalised feeders and consume a large variety of plants, grasses, trees and fruits. By using their trunks they can obtain food anywhere from ground level to high up in the trees. If they can't reach it and they still want it, they just bulldoze the tree until it falls over. They can spend up to 16 hours a day feeding and consume approx 4 - 8% of their body weight each day.
Their digestive system is quite simple and common among mammals. On average it takes an elephant 24 hours to digest a meal. However, they only digest approx 40% of their food intake with the remaining food passing undigested.

Feet/Toenails

Elephants are very sure-footed and have fantastic balance. Although an elephant appears to be flat-footed, it actually walks on its toes. The heel is a pad of fatty and elastic connective tissue. As an elephant walks, its feet, under weight and pressure bulge like a large suction cup, and then as it sets off, this bulging retracts so the foot does not get stuck in muddy or boggy terrain. Asian Elephants have five nails on each front foot and four nails on each rear foot.

Ears

Elephants have excellent hearing. They communicate and are able to pick up sounds well below the range of human hearing. This sound is called 'infrasound'. The ears also function as cooling devices. The skin on the ears is only a few millimetres thick which is the thinnest on an elephant's body. By flapping their ears an elephant can cool the blood running through the extensive vein network on the back of the ears thereby dissipating heat. Asian Elephants have smaller, triangular ears.

Trunk

An elephant's trunk is the most versatile appendage in the animal kingdom. The trunk of an Asian Elephant has one finger-like tip, located on the dorsal side of the trunk. The trunk is connected to respiration and can be used as a snorkel when swimming, as a straw for drinking and as both a knife and fork when eating. An elephant's trunk can pick up something as small as a peanut and as big as a tree trunk. It also assists in communication, dusting, smelling, lifting, defence and offence. An elephant's trunk contains no bones or cartilage and recent research work suggests that there are over 40,000 muscle units within the trunk itself. Measurements show that the trunk of an adult Asian Elephant can hold almost 9 litres of water and a thirsty adult bull can drink over 200 litres of water in less than five minutes.

A young elephant must learn how to use its trunk just children learn to use their arms and hands.

Elephant Differences

Breeding

Elephants mature sexually between the ages of 8 - 10. However, this is dependant on diet and environment. A plentiful food supply and no environment stresses such as droughts mean some elephants can reproduce at younger ages. There are recorded births from elephants as young as six years old in captivity.

Female elephants cycle every 14 - 17 weeks and once pregnant, give birth to a single calf (twins are very rare) after a gestation period of almost 22 months.
Whilst young elephant males may be eager and willing to breed they may not be in a position to do so until they are able to assert their dominance through size and strength over other males. This could be well in to their late 30's and 40's. Adult male elephants (bulls) go through periods of heightened sexual activity, increased aggressive and sexual behaviour, secretions from glands on the side of the head (temporal glands) and urine dribbling. This is known as musth. Musth is usually associated with increased secretion of testosterone and may last for periods of a few weeks to months. Bulls do not have to be in musth to breed successfully.

There is one official report of a male African and female Asian Elephant interbreeding in 1979, however the calf died 10 days after birth.