The 1,300km journey, which captured the nation’s attention three years ago, is a reminder of the need to protect the habitat of Asian elephants.
Remember the “Short-trunk Clan”, named after the herd member with a shorter-than-usual trunk?
In March 2020, an elephant matriarch led a dozen or so other elephants out of the Xishuangbanna National Nature Reserve in south Yunnan province, on a northbound expedition which would take them all the way to the provincial capital, Kunming, and back again. They were on the move for 17 months, covering more than 1,300 km before reaching home in August 2021 and completing what the media dubbed their “fantastic journey”. The elephants attracted worldwide attention for their travels and became an internet sensation.
World Elephant Day this year, on 12 August, marked the third anniversary of the Short-trunk Clan’s trek. A number of studies have shed light on factors that led the elephants to up sticks and leave. The protection and expansion of habitats have been identified as keys to mitigating the need for such extreme journeys.
External causes: Could drought be key?
It is not uncommon for China’s Asian elephants to wander off from where they live. The Short-trunk Clan’s odyssey started in a part of the Xishuangbanna reserve known as the Mengyang sub-reserve. A movement of elephants out of Mengyang had been recorded as early as 1995, when five elephants roamed northwards towards Pu’er City, and there have been at least nine such movements subsequently.
However, the northward trek of the Short-trunk Clan was the first time Asian elephants in China have been observed journeying north over such a distance; even experts were perplexed as to the cause and purpose of the trek. Professor Chen Mingyong, head of the Asian elephant research centre at Yunnan University, told the media: ”The herd are wandering haphazardly, but always northwards, and because they are gaining altitude as they go north, there is less and less food available for them on the wooded slopes. It’s extraordinary behaviour.”
Pan Wenjing, forest and oceans project manager at Greenpeace East Asia, has focused on Asian elephants for years, and her organisation has worked on habitat conservation. She explains that it is normal for elephants to move with the seasons between different habitats, but the distance the Short-trunk Clan covered is unprecedented: “It’s a singular event and cannot easily be attributed to a particular reason,” Pan notes.
The elephants’ wanderings caught the attention of scholars, including researcher Haijun Wang from Yunnan University’s School of Ecology and Environmental Science.
Between March and August 2020, more than 300 African elephants died in Botswana. A study by Wang and a team of researchers showed that sustained high temperatures and drought conditions had spurred the growth of blue-green algae in water sources, producing cyanotoxins, which led to the mass death of elephants.
Wang told China Dialogue: “The northward movement of Asian elephants in Yunnan and the mass death of African elephants in Botswana, both of which happened around the same time, took place approximately 24 degrees north and south of the equator respectively. We inferred from this that persistent high temperatures and drought conditions could be environmental stressors that both species face in common.”
In another paper, also published in 2021, Wang and his co-authors identified a combination of factors behind the elephant herd’s northward movement. Among them was the sharp drop in herbaceous and shrubby vegetation inside the reserve, brought on by extreme dry heat conditions beginning in 2019, which aggravated a shortage of food for the elephants and was very likely what induced them to set off.
Official dispatches record that Xishuangbanna experienced moderate drought in 2019, while 2020 brought an increase of drought, across much of Yunnan, due to high temperatures and low rainfall. 57 of the province’s rivers ran dry, hampering access to potable water for about a million people and hundreds of thousands of livestock.
In the documentary Walking with Elephants, which records the odyssey of the Short-trunk Clan, Shen Qingzhong, director of the Institute of Ecology at Xishuangbanna National Nature Reserve, says: “2020 is the driest year on record in Xishuangbanna … The river alongside Wild Elephant Valley ran dry in February, after Chinese New Year. Never before in history has that happened.”
Making matters harder for elephants is their enormous appetite: an adult consumes 100–300 kg of food and 80–200 litres of water every day. With drought reducing the availability of both food and water, it is only logical that elephants would seek out new areas more suitable for them.
The extended migration of elephants can also be seen in other parts of the world. In India, Asian elephants have been observed moving long distances on account of severe drought, and it is quite common for African elephants to leave reserves during the dry season.
Internal factors: Elephants’ adaptation to environment and climate
However, Wang also emphasises that while “water and food problems brought on by drought are factors inducing elephants to leave their original habitat, they do not determine the direction the elephants take.”
The northbound Short-trunk Clan was only one of at least three groups of elephants to depart their habitats in 2020 and 2021. Around the same time that it began to wander, another group from the Mengyang area, comprising the 17 members of the “Small Missing-ear Clan”, took to the road. That group headed south, however, and in May 2021 lumbered into the Xishuangbanna Tropical Botanical Garden of the Chinese Academy of Sciences. A third group, meanwhile, entered villages next to the reserve to feed on fruit.
A study released in 2022, with Fei Chen, director of the National Forestry and Grassland Administration’s Asian Elephant Research Centre, as one of its co-authors, concluded that the elephants’ trek was not a migration so much as it was partial and irruptive nomadic behaviour, as well as being a failed effort at dispersal. The Short-trunk and Small Missing-ear groups acted in response to abnormal conditions, in the form of drought, and could therefore be said to have made an understandable choice.
Elephants are intelligent creatures that adapt to food-limiting changes in the environment –such as drought, flooding, forest fires, and invasive species – by changing their own patterns of activity. Climate change, meanwhile, can increase the frequency of such phenomena.
Climate change and protections for areas of human habitation have driven an expansion in the range of Asian elephants in Yunnan, found a team of researchers analysing changes in their distribution between 1959 and 2021. Specifically, the warmer the temperature and the higher the density of human residents, the more the herds drift towards higher latitudes, which means heading north. And under climate change scenarios for 2021 to 2030, Asian elephants are forecast to spread north-east from their current range.
However, not all elephants are able to make climate and environmental adaptations in time.
In 2022, 179 elephants in a Kenyan national park died within an eight-month period due to drought.
A study of Asian elephants in Myanmar notes that climate change is increasing the risk of infectious diseases and drought, and making it harder to access water – which is likely to raise mortality.
The possibility of elephants advancing and people withdrawing
The Asian elephant remains a Class I state-protected animal in China – the highest classification in the country – with only about 300 remaining in the wild, fewer than even the number of giant pandas. It is also listed as “Endangered” by the International Union for Conservation of Nature (IUCN).
China’s Asian elephants are mainly found in the prefecture of Xishuangbanna and the municipalities of Pu’er and Lincang, all in Yunnan. In 1958 and 1980, the Xishuangbanna and Nan’gunhe national nature reserves were set up in Yunnan, covering 4,253 square kilometres (sq km), with the Asian elephant as one of the main focuses for conservation. The reserve in Xishuangbanna, home to the Short-trunk Clan, comprises five discontinuous sub-areas – in Mengyang, Menglun, Mengla, Shangyong and Mangao.
The biggest threat elephants face is habitat loss due to human activity. Professor Zhang Li, from the College of Life Sciences at Beijing Normal University, wrote in 2017 that the expansion of commercial forest plantations and replacement of natural forests with plantations for rubber and tea, among other agricultural commodities, has led to elephant habitats shrinking and seriously fragmenting.
Habitat problems have been a matter of discussion throughout history. In The Retreat of the Elephants, a classic work on Chinese environmental history published in 2004, historian Mark Elvin analysed the settlement and dispersal of humans in terms of a struggle against elephants on three fronts: over the clearing of land for farming; over the protection of crops; and over ivory and the use of elephants for war, transport and ceremony. Destruction of habitat was decisive in that struggle, and it led to elephants being forced further south.
This is true not only for China. An assessment of changing forest habitat for Asian elephants has shown that more than 67,000 sq km of it was lost from 2001 to 2018. Of this loss, 87% was directly attributable to logging and deforestation associated with the expansion of farming and plantations, while the remaining 13% was lost to mining, urban growth and infrastructure development.
Climate factors in elephant habitats
In the past three years, the Short-trunk Clan has grown in number, with calves being born and new adult males joining. The clan also split into two groups that are active in different areas, which is welcome news in the context of the global decline in Asian elephant numbers. But an increasing elephant population means that herds need to range further afield in search of food, which brings urgency to addressing the issue of conserving and potentially expanding their habitats.
In a briefing on the herds, Wan Yong, director of Yunnan’s Forestry and Grassland Administration Bureau, said that years of conservation have seen China’s population of wild Asian elephants grow from around 150 in 1978 to more than 300 now. By the end of 2020, elephant presence had spread beyond the Xishuangbanna and Nan’gunhe nature reserves to 55 townships in 11 counties across three prefectures and cities in Yunnan, with much of the elephants’ activity taking place outside of nature reserves. Moreover, forest cover in the Xishuangbanna reserve had reached more than 97% by 2016, with a high level of canopy closure and a reduction in plants for elephants to feed on.
If conditions in the elephants’ original habitat do not improve, instances of them leaving and dispersing more widely are likely to become more frequent, says Pan Wenjing. During the past few years, China’s government has accelerated the introduction of protections for Asian elephants. Experts have been calling for conservation areas to be expanded, forest plantations to be converted to ensure availability of food for elephants, ecological corridors and food source bases to be developed, and cross-border conservation areas to be established. A national park for Asian elephants is also being created.
A paper published in 2019 concluded that China had about 5,228 sq km of suitable habitat for Asian elephants, and that this will fall by 2,391 sq km – more than 45% – by 2050, due to climate change. The paper’s lead author, Dr Li Wenwen, argues that suitable elephant habitats need to either be protected from human activity, or be identified as “climate refugia” – areas of relatively stable climatic conditions and good connectivity to current and future suitable areas. “The main thing [to ensure] the survival of Asian elephants is to restore and expand suitable habitats for them”, says Li.
For Haijun Wang, achieving harmonious human–elephant coexistence against a backdrop of global climate change is something that needs exploring in depth. He said: “The main point of friction between humans and elephants at present is still the conflict over land to live on. In the future, we have to give priority consideration to the food and water needs of the growing population of Asian elephants, as well as the impact of weather extremes on their food and water resources.”
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