Asian Elephant

Asian elephants are herbivores that eat a variety of plant material, including grass, leaves, branches, bark, roots, fruits, flowers, and seeds of over 100 different species of plants. Their agile trunk plays a major role in the diverse plant options because it allows them to grasp many types of food.

At the Zoo, elephants receive hay, grain, produce, and assorted browse items. Hanging hay feeders and other enriching food dispensers ensure that elephants can forage throughout the day.

Historically, Asian elephants had a very large range extending as far west as current day Iraq, as far north as the Yangtze River in China, and across the Indian subcontinent and Southeast Asia, including the islands of Sri Lanka and Sumatra (Indonesia). This geographic range was about 3.5 million square miles – about the same size as Canada.

The current geographic range is less than 200,000 square miles, which is about the size of California and only about 5% of the historical range. They can now be found in fragmented areas in India and Southeast Asia.

Asian elephants inhabit a wide range of grasslands and forest types, including scrub forest, rainforest and semi-cultivated forests, preferring areas that combine grass with low woody plants and trees.

The only natural predators of Asian elephants are tigers, which attack calves. Adult elephants are very large and males have tusks, making it dangerous for predators to attack. To avoid predation, younger elephants stay towards the center of a group, which provides protection.

The greatest threats to Asian elephants include habitat loss and fragmentation, human-elephant conflicts, and poaching. The spread of human settlements, industry, farming, and mining has led to deforestation on a large scale, leaving smaller pockets of undisturbed natural habitat for elephants. As elephants attempt to use traditional migratory routes in search of food they must leave these pockets, resulting in increased contact with humans. Asian elephants may cause damage to crops or property, resulting in humans defending their livelihoods through lethal methods. Poaching for ivory, skin, and meat and the illegal live trade of elephant calves also negatively affect the already dwindling populations.

Asian elephants have thick, gray skin that is covered with hair. Calves have thicker brown hair, but hair generally becomes sparser as they age. In some places the skin on an elephant is 1 to 2 inches thick and alone can weigh as much as 10% of their bodyweight. The skin plays a role in regulating body temperature, as do the ears. Each elephant's ear is unique and is used as a type of fingerprint for identification. The ears are full of blood vessels and act as radiators. As the ears are flapped the resulting breeze cools the blood and so helps maintain/lower the body temperature.

Asian elephants have one small finger-like projection at the end of the trunk. These "fingers" are very sensitive and make it possible for these huge animals to pick up very small objects. In addition, the more than 100,000 muscles in the trunk make it very flexible and strong enough to lift whole trees. Elephants don't drink with their trunks, but use them as "tools" to drink with. This is accomplished by filling the trunk with water and then using it as a hose to pour it into the elephant's mouth.

The elephant’s foot is formed in such a way that it is essentially walking on tiptoe, with a tough and fatty part of connective tissue for the sole. This spongy "shock absorber" helps an elephant to move silently. The sole of the foot is ridged and pitted; this contributes to the sure-footedness of the elephant for a large variety of terrain. The foot's structure allows an elephant to walk in deep mud without difficulty, because when it is withdrawn the circumference becomes smaller, reducing the suction.

Only male Asian elephants have visible tusks; females possess small incisor teeth called "tushes," which are rarely seen. Elephants use their tusks for digging, tree bark removal, maneuvering fallen trees and branches, marking, resting, and territorial fighting. Elephants are left or right “tusked”, just as humans are left or right-handed.

Mating occurs year-round, but there is more breeding during the times of peak rainfall in some areas. This is most likely related to the increased availability of food during the rainy season. Males are ready to mate at 10 to 15 years old, while females are ready at about 12 to 14 years old.

Bull elephants (adult males) go through periodic episodes of elevated testosterone and heightened aggressive states called “musth”. During this period, male elephants show an increase in chemical signaling, visual displays of dominance, and low-frequency vocalizations to attract female elephants. To undergo musth, males need to be in good physical condition and consume an increased amount of food. They use their tusks in combat to compete for mates. Males in musth usually win fights over those that are not, making it crucial for their reproductive success. Female elephants prefer mates in musth because it indicates that they are the most dominant and strongest mates. Musth strength increases with age, so younger males may not gain access to breed until they are more mature.

The length of pregnancy, or gestation time, is close to two years. A female will normally give birth to just one offspring that can weigh up to 300 pounds at birth. Asian elephants display allomothering, where individuals other than mother provide care. Other females in the group, usually individuals related to the mother, help raise the calf. The calf may continue to drink its mother’s milk until about 4 years of age, but it is not required for survival beyond 2 years of age. Asian elephants breed every 4 to 5 years, but this is highly variable based on food availability, the presence of a suckling calf, and the female’s age.

Asian elephants communicate with visual and chemical signals, sound, and touch. Their vision is relatively weak, but visual signals are still important in communication. Elephants use the trunk tip as a chemical receptor, allowing them to obtain information about other elephants. They gather chemical information by touching the trunk tip against a biological substance from another elephant, then pressing it against the roof of the mouth to the vomeronasal (or Jacobson's) organ where the chemical is analyzed. This is known as the Flehmen Response.

Elephants can make many types of vocalizations that can travel short and long distances. They can produce sounds in the infrasound range, which have frequencies below the levels humans can hear. Their trunks and feet can pick up on vibrations through the ground. Elephants are very sensitive to each other, touching each other frequently with their trunks.

Asian elephants are a nomadic species, moving frequently to access food resources to sustain their large size. They spend 12 to 18 hours searching for and eating food – eating about 10% of their body mass daily. They live in hot climates and will often spend the hottest hours of the day in the shade and being less active. If water is available, they will submerge themselves in water or use their trunks to spray water on themselves to keep cool. They are excellent swimmers and can submerge their bodies leaving only the trunk out of the water to breathe, like a snorkel. Elephants will also cover themselves in mud or dirt to keep cool and help with insect control.

Elephants are extremely sociable and occur in groups of related females and their young offspring, led by the oldest female known as the “matriarch”. Males leave herds once they reach maturity, usually around 14 years old, and travel alone or in bachelor groups.