Alien Invasion: Protecting biodiversity by controlling invasive species in Sri Lanka
Located 245 kilometres southeast of Sri Lanka’s capital, Colombo, Bundala National Park is an internationally important wintering ground for migratory water birds.
Bundala is not solely a paradise for migratory birds, it is also a haven for significant biological diversity. However, this natural wealth is under threat from invasive non-native species. These non-natives grow rapidly and compete vigorously, pushing out native species and altering ecosystems.
Bundala harbors 197 species of birds, the highlight being the greater flamingo, which migrates in large flocks. Bundala was designated a wildlife sanctuary in 1969 and rechristened as a national park on 04 January 1993. In 1991, Bundala became the first wetland in Sri Lanka to be declared a Wetland of International Importance under the Ramsar Convention on Wetlands. In 2005, the national park was further declared a biosphere reserve by UNESCO, making it the fourth such biosphere reserve in Sri Lanka.
Hardy pest species such as Prosopsis cineraria (a flowering tree in the pea family, locally known as Kalapu andara) and Opuntia dillenii – or spiny pest pear cactus - have invaded large portions of Bundala and are threatening to overtake indigenous plant species. Aquatic areas are under siege from the narrowleaf cattail reed and Guam.
In response, the project, Strengthening capacity to control the introduction and spread of alien invasive species in Sri Lanka, is building capacity across sectors in Sri Lanka, in order to safeguard globally significant biodiversity. Financed by the Global Environment Facility, and supported by UNDP in partnership Sri Lanka’s Ministry of Mahaweli Development and Environment, the project is working to protect the ecological services from biodiversity that are necessary for livelihoods and agricultural production. By protecting the farming sector, the project is protecting those whose livelihoods depend on healthy ecosystems.
The project also contributes to the global environment by safeguarding Sri Lanka’s globally important biodiversity, including reducing the risks to endemic species, unique and threatened ecosystems, and protected areas.
Mr. Prashantha Wimaladasa, Assistant Director to the Wildlife Conservation Department (South), notes Kalapu andara has spread more aggressively than other plants. Thirty five percent of the land area we have identified is covered with plants such as thorny shrubs and large trees. Among these Kalapu andara has spread in over 2000 acres.”
Due to the tree’s ability to resist drought and soil salinity, it spread widely, overtaking other plant species and covering large swathes of land with dense, thorny foliage which is harmful to indigenous species. To make matters worse, the Kalapu andara upper canopy serves to incubate the spiny pest pear cactus in the lower canopy, resulting in an impenetrable, uninhabitable mass of brambles, totally inhospitable to native species and threatening the nascent eco-tourism industry.
According Sarath Gamini Galappaththi, a tourist guide in Bundala:
“I’m 50 years old and during these 50 years the tourist industry of this village existed beautifully well. But there are no facilities now to continue this industry due to plants such as kalapu andara and spiny pest pear, and others. Also the lagoons and lakes are covered with Guam, Hambu, Kura and have spread throughout. Migratory birds used to come here but they do not come any more to our village areas. As a result our industry is falling apart and families that have depended on this industry are also falling apart.”
The losses to animal forage and migratory routes for land animals has, in turn, displaced native fauna and impinging on local agriculture.
“This jungle has only Kalapu andara and spiny pest pear. Therefore the animals have nothing to eat. That’s why they trouble the villagers. I had planted water melon last time, and the water melon cultivation was totally destroyed. The wild boar, deer, monkeys all come and destroy our farmlands.” W.H. Premarathne – Farmer, New City Village, Waligaththa.
The plague of hungry, marauding elephants still pales in comparison to the scourge of the narrowleaf cattail reed. The Hambu reed produces prodigious volumes of hairy seed capsules, which burst open during the dry season and are spread by the wind, deluging local villages in with choking fibres.
“The spread of the Hambu reed is very troublesome to our children. The children’s parents have to come daily and clean up this place. It is a real problem. The possibility of children getting sick has increased. Day by day with this dry climate due to the spread of Hambu the percentage of children's attendance has also dropped. “ J.K. Kusumawathi- Main Matron , Sucharitha Pre-school, Uruniya.
“I can’t even cook and keep any food because of the downs coming from the Hambu reed. They get stuck in the cooking pans causing illnesses. The most serious disease the children of our village have is asthma. It is caused by the germs spread by the downs. If we go to a doctor most suffer from illnesses related to this.” H.G. Priyanthi – Siriyagama , Hambanthota.
“We can see the Hambu plant mostly spreading close to water logged areas around Bundala. There is an increase in respiratory diseases because of the spread of its inflorescence during the dry period. We can see an increase of children being brought to clinics during the past few years due to respiratory problems causing diseases such as epilepsy.” Dr. Chaminda Kurukulasuriya – Medical Officer, hospital, Debara Lake.
The prevention and control of these invasive, exotic species requires careful planning and rigorous protocols. When not done correctly, invasive species removal risks spreading the plants further. Procedures for Kalapu andara and spiny pest pear include full uprooting, drying, and burning.
“For a period of 8 years we have been methodically removing kalapu andara and spiny pest pear in the Bundala National Park by following correct procedures. We are also hoping to continue these methodologies in the future.” Ruwan Sanjeewa – Sectional Head, Linea Aqua company
“A national policy is prepared by us for the management of invasive foreign biological species under the Mahaweli Development and Environment Ministry. This national policy contains a policy statement and a strategy as well as an action plan. Through these activities we work to identify appropriate activities for management of the removal of invasive plants in the National Park and to implement these activities.” R.H.M.Abeykoon – Director, Biodiversity secretarial office
UNDP is committed to building the capacities of developing countries to manage their biodiversity and to secure ecosystem services that are vital to human welfare and sustainable development efforts. UNDP is currently supporting 400 projects to strengthen protected area systems, to mainstream biodiversity in national and local development and fiscal planning processes and production sector planning and operations, and to promote ecosystem based climate change mitigation and adaptation in over 130 countries.
For more information on the project, please visit here.
This story was originally published on UNDP Exposure.
Story by Andrea Egan, Shyara Bastiansz, UNDP Sri Lanka / Photos: UNDP Sri Lanka