Asian Elephant
Weight:
Females average 2720 kg (5980 lb ). Large bulls weigh 5400 kg (11,900 lb) (Nowak 1999).
Habitat:
The Asian elephant currently occupies forested habitats in hilly or mountainous terrain, up to about 3600 m (11,800'). It is adaptable and can occur in a wide range of habitats, from thick jungles to grassy plains
The Asian elephant occurs in the Peninsular Malaysian Lowland & Montane Forests, Northern Indochina Subtropical Moist Forests, Sri Lankan Moist Forests, Kayah-Karan/Tenasserim Moist Forests, Western Ghats Moist Forests, Annamite Range Moist Forests, Eastern Indochina Dry & Monsoon Forests, and Eastern Indian Monsoon Forests Global 200 Ecoregions. (Olson & Dinerstein 1998, Olson & Dinerstein 1999)
Age to Maturity:
Female Asian elephants attain sexual maturity when 9-12 years old. Males are capable of reproduction at 10-17 years, but they are still too young to dominate older females and do not significantly contribute to reproduction. Sexual maturity may be delayed for several years during drought or periods of high population density.
Gestation Period:
Approximately 22 months.
Birth Rate:
One calf is born at a time. A female may produce a calf every 3 - 4 years, although this period may be extended when conditions are unfavorable for survival, such as during drought.
Fecundity:
Age 0 - 15: 0.0 (births/female/year); age 16 - 50: 0.225 (births/female/year); age 51 - 60: 0.20 (births/female/year) (Sukumar et al. 1998).
Early Development:
There is a long period of juvenile dependency. The infant suckles for 3 - 4 years.
Dispersal:
Young males appear to leave the family group and become solitary at about the time they become sexually mature.
Maximum Reproductive Age:
The period of greatest female fecundity is between 25-45 years.
Maximum Age:
Sixty years in the wild (more than 80 years in captivity).
Diet:
The Asian elephant eats grasses and small amounts of leaves, woody parts of trees and shrubs - twigs, branches and bark. Cultivated crops, such as bananas, paddy and sugar cane are also preferred, with the result that the elephant often becomes a pest in agricultural regions. It will also eat large quantities of flowers and fruits when these are available and will dig for roots, including bamboo.
Social Organization:
The Asian elephant is gregarious, and, although males sometimes live alone, females are always found in family groups consisting of mothers, daughters, sisters and immature males. In the 19th century, these family groups usually consisted of 30 - 50 animals, but much larger groups, as large as 100 individuals, were not uncommon. Sometimes an adult male can be associated with a herd. When not, adult males usually remain solitary and disperse over relatively small, widely overlapping home ranges; sometimes they gather together in small but temporary bull herds. They do not seem to be territorial, and there is a great amount of toleration between them, except possibly when the cows are in estrus.
Mortality/Survival:
Female mortality by age class: <1 year: 0.10; 1 - 5 years: 0.04; 6 - 15 years: 0.015; 16 - 20 years: 0.03: 21 - 50 years: 0.015; 51 - 60 years: 0.10. Male 'natural' (i.e. unpoached) mortality by age class: <1 year: 0.15; 1 - 5 years: 0.06; 6 - 50 years: 0.08; 51 - 60 years: 0.15. (Sukumar et al. 1998)
Minimum Viable Population:
Estimated Minimum Viable Population Density: 0.31 individuals/sq km (0.8 individuals/sq mi). (Silva & Downing 1994)