Are Elephants Learning New Lessons in the Changing Environment?

COMMENTARY Wanderers of Rajaji: are elephants learning new lessons in the changing environment? Ritesh Joshi Factors which influence learning of ridors in India revealed that the presence and the Asian elephant15. However, only behaviour in wild animal populations are of traffic on the road, construction of few studies have been conducted on the important for understanding the re- steep retaining walls and human popula- social organization of Asian elephants sponses of species to changing environ- tion along the entire Rajaji–Corbett wild- throughout their range. Future studies ments and for their conservation1. An life corridor area have almost restricted should focus on a better understanding of important and often neglected aspect of the migration of elephants between the the social organizations of Asian ele- behavioural ecology concerns the ability Rajaji and Corbett National Parks11. The phants. Despite the fact that RNP is one of animal populations and individuals to northwestern elephant population in of the crucial and biologically rich pro- respond to changes in their immediate India once had a continuous range, from tected areas, little has been done on the environment, both on long- and short- Katerniaghat Wildlife Sanctuary in the behaviour of Asian elephants. In con- term basis2. Asian elephant (Elephas east, to the Yamuna river in the west; trast, several studies have been con- maximus) is one of the flagship species however, over the time this continuity ducted on the movement and status of in the Indian forests, which requires has been broken, and now the whole ecological corridors of the elephants, large landscapes for movement, feeding, population occurs in six isolated sub- which revealed their movement pattern etc. Connectivity of large migratory cor- populations12,13. Though RNP has been in the entire Rajaji–Corbett National ridors helps the elephant to move across recently notified as the Rajaji Tiger Re- Parks11,16,17. While studying elephants in larger landscapes and breed conven- serve to enhance conservation activities, the northwestern Shivalik landscape for iently, ensuring its long-term survival. providing a natural connectivity for fre- about a decade, the present article obser- However, the population of this giant quent movement of elephants has been ved a few of their behavioural responses, animal remains fragmented and restricted one of the major challenges. RNP has which revealed that the elephants were to the foothills-dominant areas, mainly been maintaining a stable population of learning to adapt themselves to fulfil because of the conversion of natural elephants for the last one and half dec- their requirements, according to the habitats in the fertile river valleys to ag- ades, with an average of 394.5 71.90 changing environment. ricultural fields, industrial areas and hu- (range 302–469) individuals14. Elephants live in a matriarchal society, man settlements3. It is now widely Various aspects of social organization where the oldest female usually leads the acknowledged that the elephants are in- have been intensively studied in African group. In contrast, bull elephants prefer telligent and learning to adapt to their savannah elephant (Loxodonta africana to lead a solitary life, especially after changing natural environments4–6. They africana), compared to the African forest attaining the pubertal stage. Male ele- possess higher levels of intelligence and elephant (Loxodonta africana cyclotis) phants are known to use a wide range of cognitive abilities, and thus are capable of exhibiting novel behavioural responses to a changing environment7. The Rajaji National Park (RNP; 2915–3031N, 7752–7822E; Figure 1) is one of the crucial wildlife habitats in the northwestern Shivalik landscape in Uttarakhand, forming the northwestern limit of the range of elephants in India. It falls within the Gangetic Plains bio- geographic zone and upper Gangetic Plains province8; and a major portion of the area is dominated by tropical moist deciduous forest. RNP is spread at an elevation of 302–1000 m and has been considered as the northwestern limit of distribution of many endangered species like the Asian elephant, tiger, great-pied hornbill and king cobra9,10. Isolation of large migratory corridors and increasing anthropogenic and deve- lopmental activities have been some of the causes threatening the survival of elephants in the area. One of the studies Figure 1. Location map of the Rajaji National Park, Uttarakhand, India indicating carried out on the status of elephant cor- important wildlife corridors and crop-raiding areas. 1808 CURRENT SCIENCE, VOL. 112, NO. 9, 10 MAY 2017 COMMENTARY habitats, and travel more distances com- recorded ranging from ~300 to 700 m. phants were familiar with these fences. pared to the family groups. They are However, above this elevation, their Elephants use twigs or branches of trees known to enter agricultural fields to feed movement was found to be rare and sea- on the fences and/or bend the iron pillars on cultivated crops and return to the sonal. During monsoon, on several occa- of the fences causing the electric current forest unharmed. While studying the sions, the present author recorded the to trip due to wet ground vegetation. behaviour of elephants in RNP, it was movement of male elephants at an eleva- They would then bend the iron pillars observed that the bull elephants arrive tion of ~980 m on the outskirts of vil- with their forefoot and cross the fence. and assemble in the forest adjacent to the lages, situated along the boundary of Similar observations were made from the agricultural fields in the afternoon and the park, mainly to feed upon palatable southern Indian elephant ranges from stay there till dusk; they enter the fields crops in these villages. A few of the where they were reported to use their by forming groups and return to the for- villages, where the movement of ele- tusks, soles of forefeet and trees to cross est before dawn. As observed, the tim- phants was recorded include Talla Banas the fence22. A study carried out by a ings of their movements entirely depend (2958384N, 7819930E; 943 m), team from World Wildlife Fund indi- on the distances which have to be cov- Kasaan (2958810N, 781710E; cated that in parts of South Asia, some ered. However, sometimes they also get 983 m) and Garakot (295429.7N, elephants eventually adapted to pro- trapped in the villages when they stay in 782219.4E; 970 m). A number of vil- longed exposure to these fences. Ele- the fields for longer duration up to dawn lages situated along the eastern boundary phants have been reported to break or when they travel long distances during of the Park grow various cash crops like electric fences using their tusks, which night and are not able to return from the paddy, wheat, maize, etc. It was also are considered to be non-conductive; and fields. In such situations, bull elephants observed during the study that elephants few elephants appeared to have learnt stay in any of the small forest patches prefer to move across higher ridges dur- that an electric shock does not harm them (islands) located in the River Ganges and ing monsoon, as all the natural water and simply barged through the wires23. sometimes in the agricultural fields. sources located across the hilly terrain Recently, similar reports from the south- It was observed during several occa- are filled with rainwater during mon- ern Indian elephant ranges showed that sions that the older bull elephants were soon, and several species of grasses like the elephants were short-circuiting the getting used to facing the crowds and Neyraudia arundinacea (Madagascar electric fences using logs24. A study in vehicular traffic pressure. The bull ele- grass), Desmostachya bipinnata (sacrifi- Africa also indicated a similar observa- phants, especially older ones, while cial grass) and Dendrocalamus strictus tion, wherein the elephants were reported crossing the national highways/motor (bamboo) grow in abundance in the high to have short-circuited the electric fences roads, were observed to show no fear of ridges of the Park. in order to gain access to crops or water any objects, whether vehicular traffic or Electric fences have been considered installation. This study observed that the the crowds (Figure 2). Sometimes, ele- as one of the effective barriers to restrict elephants had learnt to protect them- phants spent a few minutes standing on elephants from entering crop fields19–21. selves against electric shock while break- the road and facing the vehicular traffic During 2006–2011, on a few occasions, ing an electrified fence using a tusk or and exhibiting mock charges to threaten observations were made from areas adja- even holding a rock to the forehead or the crowds standing there. A study car- cent to the Shyampur and Chiriapur throwing a tree into the fence25. Another ried out on the life history of male Afri- forests of Haridwar Forest Division, study in Sri Lanka reported that the elec- can elephants suggested that older males Uttarakhand, that some of the bull ele- tric fence could not prevent the elephants were more likely to be raiders than young males, when their closest associates were also raiders and when their second closest associates were raiders older than them1. Another study carried out in the northwestern Shivalik landscape on the social bonding of male elephants indicated that the bull elephants in the area have a year round association, mainly during their movements outside the boundaries of protected habitats and during raiding of crops18. Individual adult and sub-adult male elephants are known to show a higher propensity of occurrence in high-disturbance areas when forming groups, whereas solitary elephants are suggested to exhibit the least propensity in such areas2. Generally the movement of elephants occurs across the higher ridges of the Park during monsoon and is confined to lowlands during winter and summer.

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