Indian Elephant | |
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Conservation status | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Family: | Elephantidae |
Genus: | Elephas |
Species: | Elephas maximus |
Subspecies: | E. m. indicus |
Trinomial name | |
Elephas maximus indicus Cuvier, 1798 |
The Indian Elephant (Elephas maximus indicus) is one of three recognized subspecies of the Asian elephant, and native to mainland Asia. Since 1986, Elephas maximus has been listed as endangered by IUCN as the population has declined by at least 50% over the last three generations, estimated to be 60–75 years. The species is pre-eminently threatened by habitat loss, degradation and fragmentation.[1]
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In general, Asian elephants are smaller than African elephants and have the highest body point on the head. The tip of their trunk has one finger-like process. Their back is convex or level.[2] Indian elephants reach a shoulder height of between 2 and 3.5 m (6.6 and 11.5 ft), weigh between 2,000 and 5,000 kg (4,400 and 11,000 lb), and have 19 pairs of ribs. Their skin color is lighter than of maximus with smaller patches of depigmentation, but darker than of sumatranus. Females are usually smaller than males, and have short or no tusks.[3]
The largest Indian elephant was 3.43 metres (11.3 ft) high at the shoulder.[4] In 1985, two large elephant bulls were spotted for the first time in Bardia National Park, and named Raja Gaj and Kanchha. They roamed the park area together and made occasional visits to the females. Raja Gaj stood 11.3 ft (3.4 m) tall at the shoulder and had a massive body weight. His appearance has been compared to that of a mammoth due to his high bi-domed shaped head. His forehead and domes were more prominent than in other Asian bull elephants.[5]
Indian elephants have smaller ears, but relatively broader skulls and larger trunks than African elephants. Toes are large and broad. Unlike their African cousins, their abdomen is proportionate with their body weight but the African elephant has a large abdomen as compared to the skulls.
Indian elephants are native to mainland Asia: India, Nepal, Bangladesh, Bhutan, Myanmar, Thailand, Malay Peninsular, Laos, China, Cambodia, and Vietnam. They inhabit grasslands, dry deciduous, moist deciduous, evergreen and semi-evergreen forests. In the early 1990s, their estimated population size was[6]
The movement and habitat utilization patterns of an elephant population were studied in southern India during 1981–83 within a 1,130 km2 (440 sq mi) study area. The area encompasses a diversity of vegetation types — from dry thorn forest at 250 to 400 m (820 to 1,300 ft) of altitude through deciduous forest (400 to 1,400 m (1,300 to 4,600 ft)) to stunted evergreen shola forest and grassland (1,400 to 1,800 m (4,600 to 5,900 ft)). Five different elephant clans, each consisting of between 50 and 200 individuals had home ranges of between 105 km2 (41 sq mi) and 320 km2 (120 sq mi), which overlapped. Seasonal habitat preferences were related to the availability of water and the palatability of food plants. During the dry months of January to April, elephants congregated at high densities of up to five individuals per km2 in river valleys where browse plants had a much higher protein content than the coarse tall grasses on hill slopes. With the onset of rains in May, they dispersed over a wider area at lower densities, largely into the tall grass forests, to feed on the fresh grasses, which then had a high protein value. During the second wet season from September to December, when the tall grasses became fibrous, they moved into lower elevation short grass open forests. The normal movement pattern could be upset during years of adverse environmental conditions. However, the movement pattern of elephants in this region has not basically changed for over a century, as inferred from descriptions recorded during the 19th century.[8]
In the Nilgiri Biosphere Reserve three elephant clans had overall home ranges of 562 km2 (217 sq mi), 670 km2 (260 sq mi) and 799 km2 (308 sq mi) in the beginning of the 1990s. During three years of survey, their annual home ranges overlapped to a large extent with only minor shifts in the home ranges between years.[9]
Elephants are classified as megaherbivores and consume up to 150 kg (330 lb) of plant matter per day.[10] They are generalist feeders, and both grazers and browsers. In a study area of 1,130 km2 (440 sq mi) in southern India, elephants were recorded to feed on 112 different plant species, most commonly of the order Malvales, and the legume, palm, sedge and true grass families. They graze on the tall grasses, but the portion consumed varies with season. When the new flush appears in April, they remove the tender blades in small clumps. Later, when grasses are higher than 0.5 m (1.6 ft), they uproot entire clumps, dust them skilfully and consume the fresh leave tops, but discard the roots. When grasses are mature in autumn, they clean and consume the succulent basal portions with the roots, and discard the fibrous blades. From the bamboos, they eat seedlings, culms and lateral shoots. During the dry season from January to April, browse constitutes a major food resource. They take both leaves and twigs preferring the fresh foliage, and consume thorn bearing shoots of acacia species without any obvious discomfort. They feed on the bark of white thorn and other flowering plants, and consume the fruits of wood apple, tamarind, kumbhi and date palm.[11]
In Nepal’s Bardia National Park, elephants consume large amounts of the floodplain grass, particularly during the monsoon season. They browse more in the dry season with bark constituting a major part of their diet in the cool part of that season.[12] During a study in a tropical moist mixed deciduous forested area of 160 km2 (62 sq mi) in Assam, elephants were observed to feed on about 20 species of grasses, plants and trees. Grasses such as Imperata cylindrica and Leersia hexandra constituted by far the most predominant component of their diet.[13]
Loss of significant extents of elephant range and suitable habitat continues; their free movement is impeded by reservoirs, hydroelectric projects and associated canals, irrigation dams, numerous pockets of cultivation and plantations, highways, railway lines, mining and industrial development.[6]
Elephant conservation in northern West Bengal has been set back due to high-levels of human–elephant conflict and elephant mortality owing to railway accidents. The railway track between Siliguri and Alipurduar passes through 74 km of various forest divisions. Every day, 20 trains run on this track at high speeds. Elephants that pass through from one forest patch to another dash against the trains and die. A total of 39 dead elephants were reported during the period of 1958 to 2008, of which ten were reported killed between 2004 to 2008.[14]
In Bangladesh, forested areas that served as prime elephant habitat have undergone drastic reduction, which had a severe impact on the wild elephant population. Habitat loss and fragmentation is attributed to the increasing human population and its need for fuel wood and timber. Illegal timber extraction plays a significant role in deforestation and habitat degradation. As a result of the shrinking habitat, elephants have become more and more prone to coming into direct conflict with humans.[15]
In Myanmar, demand for elephant ivory for making tourist items is higher than ever before. The military government shows little interest in reducing the ivory trade, while the elephants in the country have become the silent victims. After the world-wide ivory ban, prices of raw ivory in the country skyrocketed from $76 a kilo for large tusks in 1989/90 to over $200 a kilo by the mid-1990s. Foreign tourists are responsible for the massive rise in price of ivory tusks which fuels the illegal killing of elephants. There is also a sizeable trade in ivory chopsticks and carvings, smuggled by traders from Myanmar into China.[16]
Elephas maximus is listed on CITES Appendix I.[1]