Elephas maximus, Linnaeus, 1758

Don E. Wilson & Russell A. Mittermeier, 2011, Elephantidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 50-79 : 78-79

3.

Asian Elephant

Elephas maximus

French: Eléphant d'Asie / German: Asiatischer Elefant / Spanish: Elefante asiético

Other common names: Pygmy Elephant (borneensis)

Taxonomy. Elephas maximus Linnaeus, 1758 ,

Sri Lanka.

Currently three subspecies of the Asian Elephant are recognized. In addition, recent genetic work has provided evidence that the elephants of Borneo, called “Pygmy Elephants,” may merit recognition as a distinct subspecies, borneensis. Phenological differences support the suggested listing, with the Borneo elephants being the smallest extant regional population. Body size, ear size, tusk straightness and size, and number of ribs offer further morphological differences between subspecies. The Sri Lankan subspecies has a large head relative to its body, pink pigmentation is more common, and most are tuskless. Sumatran elephants, sumatranus, are smaller than the other subspecies (except the Borneo elephants) and have 20 as opposed to 19 ribs.

Subspecies and Distribution.

E.m.maximusLinnaeus,1758—SriLanka.

E.m.indicusG.Cuvier,1798—India(isolatedpopulationsinS,N&NE),Nepal,Bhutan,Bangladesh,SChina,Myanmar,Laos,Cambodia,Vietnam,Thailand,andMalaysia.

E. m. sumatranus Temminck, 1847 — Indonesia (Sumatra & NE Borneo).

Descriptive notes. Head—body 550-640 cm, tail 120-150 cm, average shoulder height (the back or head are typically the highest points) is 270 cm (maximum up to 340 cm) in males and 240 cm (maximum over 250 cm) in females; average weight around 3600 kg (maximum up to 6000 kg) in males and 2720 kg (maximum 4160 kg) in females. Most of these metrics are from Asian Elephants in India, which tend to be larger than populations farther east. Borneo’s elephants are the smallest, up to half a meter shorter than the average Asian Elephant. Elephants from Asia have sparse body hair, although more than African elephants, and are typically categorized as hairless. Skin color is dark gray, but often non-pigmented regions on the ears, face, and trunk appear pink. Sri Lankan elephants are noted for being less pigmented, and in captivity lack of pigmentation has been found to correlate with stress. Asian Elephants have large angular ears critical for thermo-regulation, though their ears are smaller than those of African elephants. Only males have tusks. Females are tuskless or have small pulpless teeth called tushes.

Habitat. As generalists, Asian Elephants inhabit grassland, tropical evergreen forest, semi-evergreen forest, moist deciduous forest, dry deciduous forested, and dry thorn forest, in addition to cultivated and secondary forests and scrublands. Current extent and habitats used are primarily a function of human distribution. Commonly, elephants are relegated to regions not suited for agriculture, such as montane forests. In such habitats, use of edge regions (both forest and bush) and grass-dominated areas appears to be common and preferred. In Sri Lanka, elephants appear to prefer grassland-dominated savanna over dense forest. Over this range of habitat types elephants are seen from sea level to over 3000 m. In the Eastern Himalaya in north-east India, they regularly move up above 3000 m in summer at a few sites.

Food and Feeding. As generalist herbivores of large size and low digestive efficiency, elephant diets include an incredible array of grass and browse species, as do the diets of their counterparts in Africa. Trunk dexterity allows high selectivity or mass ingestion of plant materials, enabling access to a variety of dietary components under a range of conditions. During the 14-19 hours a day of feeding, up to 150 kg of wet weight forage may be consumed. In southern India, over 82 plant species were recorded in the diet (59 woody plant species and 23 grass species) and a study in Sri Lanka found more than 60 species ingested. Across a number of populations, preference for grasses has been demonstrated, although dominance of a grass-based diet depends on availability. Otherwise, leaves,fruit, stalks, and seeds are often dietary components. Diets vary across the year, apparently in relation to forage phenology and quality. In southern India, one site recorded dry season diets consisting of 70% browse and wet season diets consisting of 55% browse. In an adjoining region, annual diet was dominated by grass (84%).

Breeding. Reproductive parameters are similar to those of African elephants, with a gestation period of approximately 22 months followed by an extensive postpartum calf rearing period that precludes reproduction. Newborns weigh 80-110 kg. Births can occurat any season of the year, though seasonal birth pulses are common in seasonal environments. As with African Forest Elephants, detailed demographic data are limited. Average intercalf intervals appear to be 4-5 years, slightly longer than in African elephants. Breeding appears to be cyclically annual with high and low reproductive years; information on seasonality of breeding within yearsis lacking though suspected. As with African elephants, males become reproductively active when in musth and itis thought musth males dominate reproduction.

Activity patterns. Circadian patterns are dominated by foraging, which comprises 17-19 hours of the day. Sleep occurs primarily in the late night, but is only for a few hours per day, as with African elephants. Midday rests are common. Peak activity appears to occur at night, but relates to the distribution ofcritical resources.

Movements, Home range and Social organization. Similar to African elephants, a hierarchical social structure is suggested for Asian Elephants. However the degree of bonding across socialtiers appears to be much lower than that found in well-described savanna systems and may be more similar to that speculated for African Forest Elephants. In part this may be due to similarities in habitat, where widely distributed resources limit the potential for consistently large aggregations. Female core social groups are genetically related (primarily being mother—calf groups), and males disperse from their natal groups and appearto settle away from their natal range. Little is known about Asian Elephant ranging patterns, but it appears home range size and daily movement patterns are smaller than those of xeric African Savanna Elephants ( Loxodonta africana ) and possibly similar in scope to those of African Forest Elephants (L. ¢yclotis), which show a high degree of individual variability. Range is typically highly restricted by human activity, which is likely a major determinant of movement behavior. The few studies that have been undertaken suggest elephant movements are largely in response to human activity and density.

Status and Conservation. CITES Appendix I. Currently classified as Endangered on The IUCN Red List, with an estimated world population of 40,000 -50,000 remaining. Once ranging from the Euphrates to the Yangtze rivers, and south to the island of Java, current range is reduced by 85% and largely fragmented. Available estimates of current range are approximately 486,000 km?, though information on both range and population size based on educated guesses. Range fragmentation and restriction are major threats to the long-term persistence of the species, and are driving increased human-elephant conflict. Currently over 60% of extant Asian Elephants are located in three regions of India where they are under heavy and increasing pressure. Ivory poaching remains a threat, with heavily poached populations having extreme sex ratios of 80 females per male (only males carry ivory). The long term impacts of such skew are not known.

Bibliography. Choudhury et al. (2008), Fernando, Pfrender et al. (2000), Fernando, Vidya et al. (2003), Owen-Smith (1988), Rasmussen & Krishnamurthy (2000), Sukumar (1990, 2003), Vidya & Sukumar (2005a, 2005b), Vidya et al. (2009).

Figures

Plato 3 Specıes Accounts

Subspecies and Distribution. E.m.maximusLinnaeus,1758—SriLanka. E.m.indicusG.Cuvier,1798—India(isolatedpopulationsinS,N&NE),Nepal,Bhutan,Bangladesh,SChina,Myanmar,Laos,Cambodia,Vietnam,Thailand,andMalaysia. E. m. sumatranus Temminck, 1847 — Indonesia (Sumatra & NE Borneo).