Connecting Terrestrial ‘Islands’ to Promote Biological Diversity

By: Janita Gurung and Pratikshya Kandel 

This year, the UN has declared ‘Island Biodiversity’ as the theme for celebrating International Day for Biological Diversity. The world’s islands are home to about 600 million people – 10 per cent of the world’s population. These islands are also home to some unique species of plants and animals that are found nowhere else in the world. For example, the kangaroo is found only in Australia, the flightless kiwi bird is found only in New Zealand, and the now extinct dodo – another flightless bird – was found only in Mauritius. Australia, New Zealand and Mauritius are all island countries.

‘Islands’ – the word generally conjures images of areas of land surrounded by water. For conservationists, islands take on another meaning when pockets of pristine land areas rich in biodiversity exist amidst intensive areas of human settlements, agriculture, or industrialization. These ‘islands’ are generally home to numerous species of plants, birds, insects, and animals. At a larger scale, many of these ecologically significant islands have been set aside as areas to protect plants and wildlife. 

Animals, particularly large animals, must move, and thus require large areas of habitat for their survival. Often times when animals travel outside their ‘islands’ of protected areas, they enter human settlements and destroy crops, livestock, and even human life, resulting in what conservationists term ‘human-wildlife conflicts’. Humans generally respond to such wildlife intrusions by exterminating them through various means – a process termed as ‘retaliatory killing.’ 

One of the methods by which the habitat of large animals can be increased is by connecting protected areas through wildlife ‘corridors’. These corridors can be instrumental in connecting fragmented habitat islands and thereby facilitate wildlife movement. Corridors also promote interbreeding which results in genetic diversity within the wildlife population.

The Kangchenjunga Landscape is one of seven landscape initiatives in the Hindu Kush Himalayas where the ecosystem approach is being used with a focus on connecting islands of protected areas through conservation corridors. This initiative is a transboundary programme involving the governments of Bhutan, India, and Nepal. The programme aims to develop connectivity between the 20 isolated protected areas in the landscape through a network of conservation corridors extending from eastern Nepal, through the states of Sikkim and northern West Bengal in India, to western Bhutan. These corridors will facilitate the movement of species such as the endangered snow leopard in the higher elevations, and Bengal tiger and Asian elephant at lower elevations.

The Kangchenjunga Landscape is part of the Eastern Himalaya ‘Biodiversity Hotspot’ where there is high biodiversity, much of which is facing severe threats from humans. The landscape hosts a significantly high number of plants and is home to at least six species of endangered animals including the snow leopard, Himalayan musk deer, Bengal tiger, Asian elephant, and one-horned rhino, among others. The trademark plant species of the landscape is the rhododendron – at least 45 species of which are found in the landscape. The landscape is also home to approximately seven million women and men, some of whom belong to distinct ethnic groups such as the Lepchas and the Walungs.

Despite the ecological significance of the Kangchenjunga Landscape, there is much we need to know about the biodiversity and socioeconomy of the region. During a recent review process for understanding the state of knowledge on biodiversity in the landscape, about 850 published and unpublished documents were recorded. The first recorded study in the landscape was conducted more than 170 years ago on the Lepchas of Sikkim by Archibald Campbell, the British political agent to Sikkim and Darjeeling in the East India Company. This was followed by the work of the notable British naturalist Joseph Dalton Hooker, who published an account of his botanical expedition in the Kangchenjunga region in two volumes of The Himalayan Journals in 1854. Subsequently, research interest in the Kangchenjunga landscape increased significantly only three decades later in the 1980s. Much of the information gathered in the area was focused on animals and plants, with the red panda being the most researched animal species in the landscape. Over 80 per cent of the research has been conducted in the Indian portion of the Kangchenjunga Landscape, only 9 per cent has been conducted in Nepal and just 4 per cent took place in the Bhutan portion of the landscape.

Why is it important to know about the biodiversity in the Kangchenjunga Landscape? There are an estimated 8.7 million species of organisms in the world. Among these, only 1.2 million species have been identified till date – representing only 14 per cent of the total biodiversity in the world. Accordingly, we have probably identified only a third of the total number of species in the Kangchenjunga Landscape. Much of the gaps in our knowledge exist in relation to species other than plants and animals, i.e. on fish, amphibians, insects, fungi, and bacteria. Not much has been done to know the status of these relatively neglected life forms. 

Knowledge about biodiversity is crucial to understanding their roles in the ecosystem and therefore for their effective management. Biodiversity is a natural capital that provides a number of ecosystem services in the Kangchenjunga Landscape, including providing food, timber, fiber and medicines – all things we depend on. It is also an important source of income for many local people living in the landscape. Therefore, gaining in-depth knowledge on biodiversity and associated ecosystem functions is extremely important for the wellbeing of the communities within the Kangchenjunga Landscape, as well as for the global community.

About the authors

Dr Janita Gurung
Biodiversity Conservation and Management Specialist, ICIMOD

Research Associate – Biodiversity, ICIMOD