The Asian elephant ( Elephas maximus), also known as the Asiatic elephant, is the only living Elephas species. It is the largest living land animal in Asia and the second largest living Elephantidae in the world. It is characterised by its long Elephant trunk with a single finger-like processing; large in males; laterally folded large ears and wrinkled grey skin that is partly on the trunk, ears or neck. Adult males average in weight and females . It has a large and well developed neocortex of the brain, is highly intelligent and self-aware being able to display behaviours associated with grief, learning and greeting. Three subspecies are recognised— E. m. maximus, Indian elephant and E. m. sumatranus.
The Asian elephant is distributed in the Indian subcontinent and Southeast Asia, from India in the west to Borneo in the east, and Nepal in the north to Sumatra in the south. It frequently inhabits , tropical evergreen forests, semi-evergreen forests, moist , dry deciduous forests and dry thorn forests. It is herbivorous, eating about of vegetation per day. Cows and calves form groups, while males remain solitary or form "bachelor groups" with other males. During the breeding season, males temporarily join female groups to mate. Wild Asian elephants live to be about 60 years old. While female captive elephants are recorded to have lived beyond 60 years when kept in semi-natural surroundings, Asian elephants die at a much younger age in captivity; captive populations are declining due to a low birth and high death rate.
Since 1986, the Asian elephant has been listed as Endangered on the IUCN Red List, as the population has declined by at least 50 per cent over the last three elephant generations, which is about 60–75 years. It is primarily threatened by loss of habitat, habitat degradation, fragmentation and poaching. The earliest indications of captive use of Asian elephants are engravings on seals of the Indus Valley civilisation dated to the 3rd millennium BC.
Three subspecies are recognised:
Sri Lankan elephants are the largest subspecies. Their skin colour is darker than of E. m. indicus and of E. m. sumatranus with larger and more distinct patches of depigmentation on ears, face, trunk and belly.
A potential fourth subspecies, the Borneo elephant ( Elephas maximus borneensis), occurs in Borneo's northeastern parts, primarily in Sabah (Malaysia), and sometimes in Kalimantan (Indonesia). It was proposed by Paules Deraniyagala in 1950, who described an elephant in an illustration published in the National Geographic magazine, but not as a living elephant in accordance with the rules of the International Code of Zoological Nomenclature. These elephants living in northern Borneo are smaller than all the other subspecies, but had larger ears, a longer tail, and straight tusks. Results of genetic analysis indicate that their ancestors separated from the mainland population about 300,000 years ago. A study in 2003, using mitochondrial DNA analysis and microsatellite data, indicated that the Borneo elephant population is derived from stock that originated in the region of the Sunda Islands, and suggests that the Borneo population has been separated from the other elephant populations of southeast Asia since the Pleistocene.
The following Asian elephants were proposed as extinct subspecies, but are now considered synonymous with the Indian elephant:
Skin colour is usually grey, and may be masked by soil because of dusting and wallowing. Their wrinkled skin is movable and contains many nerve centres. It is smoother than that of African elephants and may be Depigmentation on the trunk, ears, or neck. The epidermis and dermis of the body average thick; skin on the dorsum is thick providing protection against bites, bumps, and adverse weather. Its folds increase surface area for heat dissipation. They can tolerate cold better than excessive heat. Skin temperature varies from . Body temperature averages .
In Bangladesh, some isolated populations survived in the south-east Chittagong Hills in the early 1990s. In Malaysia's northern Johor and Terengganu National Park, two Asian elephants tracked using satellite tracking technology spent most of their time in secondary or "logged-over forest"; they travelled 75% of their time in an area less than away from a water source. In China, the Asian elephant survives only in the prefectures of Xishuangbanna, Simao District and Lincang of southern Yunnan. , the estimated population was around 300 individuals.
As of 2017, the estimated wild population in India account for nearly three-fourths of the extant population, at 27,312 individuals. In 2019, the Asian elephant population in India increased to an estimated 27,000–29,000 individuals. , the global wild population was estimated at 48,323–51,680 individuals.
Cows and calves move about together as groups, while bulls disperse from their mothers upon reaching adolescence. Bulls are solitary or form temporary "bachelor groups". Cow-calf units generally tend to be small, typically consisting of three adults (most likely related females) and their offspring. Larger groups of as many as 15 adult females have also been recorded. Seasonal aggregations of 17 individuals including calves and young adults have been observed in Sri Lanka's Uda Walawe National Park. Until recently, Asian elephants, like African elephants, were thought to be under the leadership of older adult females, or matriarchy. It is now recognized that cows form extensive and very fluid social networks, with varying degrees of associations between individuals. Social ties generally tend to be weaker than in African bush elephants. Unlike African elephants, which rarely use their forefeet for anything other than digging or scraping soil, Asian elephants are more agile at using their feet in conjunction with the trunk for manipulating objects. They can sometimes be known for their violent behavior.
Asian elephants are recorded to make three basic sounds: growls, squeaks and snorts. Growls in their basic form are used for short distance communication. During mild arousal, growls resonate in the trunk and become rumbles while for long-distance communication, they escalate into roars. Low-frequency growls are infrasonic and made in many contexts. Squeaks come in two forms: chirpings and trumpets. Chirping consists of multiple short squeaks and signals conflict and nervousness. Trumpets are lengthened squeaks with increased loudness and are produced during extreme arousal. Snorts signal changes in activity and increase in loudness during mild or strong arousal. During the latter case, when an elephant bounces the tip of the trunk, it creates booms which serve as threat displays. Elephants can distinguish low-amplitude sounds.
Rarely, Bengal tiger have been recorded attacking and killing calves, especially if the calves become separated from their mothers, stranded from their herd, or orphaned. Adults are largely invulnerable to natural predation. There is a singular anecdotal case of a mother Asian elephant allegedly being killed alongside her calf; however, this account is contestable. In 2011 and 2014, two instances were recorded of tigers successfully killing adult elephants; one by a single tiger in Jim Corbett National Park on a 20-year-old young adult elephant cow, and another on a 28-year-old sick adult bull in Kaziranga National Park further east, which was taken down and eaten by several tigers hunting cooperatively. Elephants appear to distinguish between the growls of larger predators like tigers and smaller predators like ; they react to leopards less fearfully and more aggressively.
Bulls will fight one another to get access to cows. Strong fights over access to females are extremely rare. Bulls reach sexual maturity around the age of 12–15. Between the ages of 10 and 20 years, bulls undergo an annual phenomenon known as "musth". This is a period where the testosterone level is up to 100 times greater than non-musth periods, and they become aggressive. Secretions containing pheromones occur during this period, from the paired temporal glands located on the head between the lateral edge of the eye and the base of the ear. The aggressive behaviors observed during musth can be attributed to varying amounts of frontalin (1,5-dimethyl-6,8-dioxabicyclo3.2.1octane) throughout the maturation process of bulls. Frontalin is a pheromone that was first isolated in bark beetles but can also be produced in the bulls of both Asian and African Elephants. The compound can be excreted through urine as well as through the temporal glands of the bull, allowing signaling to occur. During musth, increased concentrations of frontalin in the bull's urine communicate the reproductive status of the bull to female elephants.
Similar to other mammals, hormone secretion in female elephants is regulated by an estrous cycle. This cycle is regulated by surges in Luteinizing hormone that are observed three weeks from each other. This type of estrous cycle has also been observed in African Elephants but is not known to affect other mammals. The first surge in Luteinizing hormone is not followed by the release of an egg from the ovaries. However, some female elephants still exhibit the expected mating protocols during this surge. Female elephants give ovulatory cues by utilizing sex . A principal component thereof, (Z)-7-dodecen-1-yl acetate, has also been found to be a sex pheromone in numerous species of insects. In both insects and elephants, this chemical compound is used as an attractant to assist the mating process. In elephants, the chemical is secreted through urination and this aids in the attraction of bulls to mate. Once detected, the chemical stimulates the vomeronasal organ of the bull, thus providing information on the maturity of the female.
Reproductive signaling exchange between male and female elephants are transmitted through olfactory cues in bodily fluids. In males, the increase in frontalin during musth heightens their sensitivity to the (Z)-7-dodecen-1-yl acetate produced by female elephants. Once perceived by receptors in the trunk, a sequence of ritualistic behaviors follow. The responses in males vary based on both the stage of development and the temperament of the elephant. This process of receiving and processing signals through the trunk is referred to as flehmen. The difference in body movements give cues to gauge if the male is interested in breeding with the female that produced the secretion. A bull that is ready to breed will move closer to the urine and in some cases an erection response is elicited. A bull that is not ready to breed will be timid and try to dissociate themselves from the signal. In addition to reproductive communication, chemosensory signaling is used to facilitate same-sex interactions. When less developed males detect pheromones from a male in musth, they often retreat to avoid coming in contact with aggressive behaviors. Female elephants have also been seen to communicate with each other through pheromone in urine. The purpose of this type of intrasex communication is still being investigated. However, there are clear differences in signaling strength and receiver response throughout different stages of the estrous cycle.
The gestation period is 18–22 months, and the cow gives birth to one calf, only occasionally . The calf is fully developed by the 19th month, but stays in the Uterus to grow so that it can reach its mother to feed. At birth, the calf weighs about , and is Lactation for up to three years. Once a female gives birth, she usually does not breed again until the first calf is weaned, resulting in a four to five-year birth interval. During this period, mother to calf communication primarily takes place through temporal means. However, male calves have been known to develop sex pheromone-producing organs at a young age. Early maturity of the vomeronasal organ allows immature elephants to produce and receive . It is unlikely that the integration of these pheromones will result in a flehmen response in a calf. Females stay on with the herd, but mature males are chased away.
Female Asian elephants sexually mature around the age of 10~15 and keep growing until 30, while males fully mature at more than the age of 25, and constantly grow throughout their life. Average elephant life expectancy is approximately 60 years. Some individuals are known to have lived into their late 80s. Generation time of the Asian elephant is 22 years.
Destruction of forests through logging, encroachment, slash-and-burn, shifting cultivation, and monoculture tree plantations are major threats to the survival of elephants. Human–elephant conflicts occur when elephants raid crops of shifting cultivators in fields, which are scattered over a large area interspersed with forests. Depredation in human settlements is another major area of human–elephant conflict occurring in small forest pockets, encroachments into elephant habitat, and on elephant migration routes. However, studies in Sri Lanka indicate that traditional slash-and-burn agriculture may create optimal habitats for elephants by creating a mosaic of successional-stage vegetation. Populations inhabiting small habitat fragments are much more liable to come into conflict with humans.
Development such as border fencing along the India–Bangladesh border has become a major impediment to the free movement of elephants. In Assam, more than 1,150 humans and 370 elephants died as a result of human-elephant conflict between 1980 and 2003. In a 2010 study, it was estimated that in India alone, over 400 people were killed by elephants each year, and 0.8 to 1 million hectares were damaged, affecting at least 500,000 families across the country.Rangarajan, M., Desai, A., Sukumar, R., Easa, P. S., Menon, V., Vincent, S., Ganguly, S., Talukdar, B. K., Singh, B., Mudappa, D., Chowdhary, S., Prasad, A. N. (2010). Gajah: Securing the future for elephants in India . Report of the Elephant Task Force. Ministry of Environment and Forests, New Delhi.Choudhury, A. (2004). Human–elephant conflicts in Northeast India. Human Dimensions of Wildlife, 9(4), 261–270. Moreover, elephants are known to destroy crops worth up to US$2–3 million annually. This has major impacts on the welfare and livelihoods of local communities, as well as the future conservation of this species. In countries like Bangladesh and Sri Lanka, the Asian elephant is one of the most feared wild animals, even though they are less deadly than other local animals such as (which were estimated to claim more than 30 times more lives in Sri Lanka than elephants).Raihan Sarker, A. H. M., & Røskaft, E. (2010). Human–wildlife conflicts and management options in Bangladesh, with special reference to Asian elephants (Elephas maximus). International Journal of Biodiversity Science, Ecosystem Services & Management, 6(3–4), 164–175.
As a whole, Asian elephants display highly sophisticated and sometimes unpredictable behaviour. Most untamed elephants try to avoid humans, but if they are caught off guard by any perceived physical threat, including humans, they will likely charge. This is especially true of males in musth and of females with young. Gunfire and other similar methods of deterring, which are known to be effective against many kinds of wild animals including tigers, may or may not work with elephants, and can even worsen the situation. Elephants that have been abused by humans in the past often become "rogue elephants", which regularly attack people with no provocation.Hoare, R. E. (1999). Determinants of human–elephant conflict in a land-use mosaic. Journal of applied ecology, 36(5), 689–700. Rasmussen, L. E. L. (1999). Evolution of chemical signals in the Asian elephant, Elephas maximus: behavioural and ecological influences. Journal of Biosciences, 24(2), 241–251. Sukumar, R. (1995). "Elephant raiders and rogues". Natural History, 104(7), 52–61.
Up to the early 1990s, Vietnamese ivory craftsmen used exclusively Asian elephant ivory from Vietnam and neighbouring Lao and Cambodia. Before 1990, there were few tourists and the low demand for worked ivory could be supplied by domestic elephants. Economic liberalisation and an increase in tourism raised both local and visitors' demands for worked ivory, which resulted in heavy poaching.
The World Elephant Day is celebrated annually on 12 August since 2012. Events are organized to divulge information and to engage people about the problems that the Asian elephant is facing. August has been established as the Asian Elephant Awareness Month by zoos and conservation partners in the United States.
Karnataka in India hosts the most Asian elephants of any known area, comprising around 20% of the total population in the country. The distribution of elephants in the state according to one estimate is roughly . In a 2013 study, an estimated 10, 000 elephants inhabited the Western Ghats, and were primarily threatened by poaching and habitat fragmentation. An increase in conflict with humans was also cited as a likely issue. Conservation plans aimed to establish wildlife corridors, stop poaching of bulls, and protect or manage land area. Project Elephant was initiated in 1992 as a Centrally Sponsored Scheme (CSS) by the Ministry of Environment, Forest and Climate Change of the Government of India. The project was initiated to protect the Indian elephant and its habitats and to establish dedicated elephant reserves for sustaining elephant populations.
The distribution of elephants in Sri Lanka is only two-fifths of what it was in the late 19th and early 20th centuries. Due to this decrease, interactions with humans occur much more frequently. During a 2003 survey, the local people expressed some form of disapproval towards the conservation of Asian elephants as farmers viewed them as pests, however, most of the participants were supportive of the idea.
In China, Asian elephants are under first-level protection. Yunnan province has 11 national and regional nature reserves. In total, the covered protected area in China is about . In 2020, the population of Asian elephants in Yunnan was estimated at around 300 individuals. As conflicts between humans and wild elephants have emerged around protected areas in the last years, the prefecture of Xishuangbanna built food bases and planted bananas and bamboo to create a better habitat.
In Thailand, Salakpra Wildlife Sanctuary and Tham Than Lot National Park are protected areas hosting around 250–300 elephants, according to figures from . In recent years the National Park has faced issues due to encroachment and over-exploitation. In India, the National Board of Wildlife recommended to allow coal mining in Dehing Patkai National Park in April 2020. The decision raised concerns between students and environmental activists who launched an online campaign to stop the project.
Demographic analysis of captive Asian elephants in North America indicates that the population is not self-sustaining. First year mortality is nearly 30 per cent, and fecundity is extremely low throughout the prime reproductive years. Data from North American and European regional from 1962 to 2006 were analysed for deviations in the birth and juvenile death sex ratios. Of 349 captive calves born, 142 died prematurely. They died within one month of birth, major causes being stillbirth and infanticide by either the calf's mother or by one of the exhibition mates. The sex ratio of stillbirths in Europe was found to have a tendency for excess of males.
Asian elephants have been captured from the wild and tamed for use by humans. Elephants can remember tone, melody, and words, allowing them to recognise more than 20 verbal commands. Their ability to work under instruction makes them particularly useful for carrying heavy objects. They have been used particularly for Lumber-carrying in jungle areas. Other than their work use, they have been used in war, in ceremonies, and for carriage. It is reported that war elephants are still used by the Kachin Independence Army (KIA) in Kachin State in northern Myanmar against Myanmar's military. The KIA use about four dozen elephants to carry supplies.
The Asian elephant plays an important part in the culture of the subcontinent and beyond, being featured prominently in the Panchatantra fables and the Buddhist Jataka tales tales. They play a major role in Hinduism: the god Ganesha's head is that of an elephant, and the "blessings" of a temple elephant are highly valued. Elephants are frequently used in parade where the animals are adorned with festive outfits.
The Asian elephant is depicted in several Indian manuscripts and treatises with notable amongst these including Matanga Lila (elephant sport) of Nilakantha. The manuscript Hastividyarnava is from Assam in northeast India. In the Burmese, Thai and Sinhalese animal and planetary zodiac, the Asian elephant, both tusked and tuskless, are the fourth and fifth animal zodiacs of the Myanmar, the fourth animal zodiac of the Thai people, and the second animal zodiac of the Sinhalese people of Sri Lanka. Similarly, the elephant is the twelfth animal zodiac in the Chinese zodiac of the Dai people in southern China.
Size
Distribution and habitat
Ecology and behaviour
Reproduction
Intelligence
Threats
Human–elephant conflict
Poaching
For ivory
For skin
Disease
Conservation
In captivity
Handling methods
In culture
See also
Bibliography
Further reading
External links
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