About the author

Rasidah Hashim was born in 1973 in a Minangkabau village near the ancient land portage of Penarikan, Negeri Sembilan, Peninsular Malaysia. A Duke University graduate in Biology (B.Sc), she later obtained her PhD in geography from the University of Cambridge in 2006. Since then she has been a lecturer in the Faculty of Environmental Studies, Universiti Putra Malaysia. Her current research interests are historical GIS, heritage conservation, forest ecology and disability advocacy. In her first contribution to EcoKnights, she explores and address issues related to the invasion of non-native plants in Malaysia and its impact on the Orang Asli communities and biodiversity conservation. For more information about issues related to this article, please feel free to email the author.

Non-Indigenous Plants and Indigenous People: Slowing the Spread of Aliens for Biodiversity Conservation

Worldwide, plant species are routinely introduced into areas outside their native range by different kinds of dispersers, including and especially humans, either intentionally or otherwise. It is widely known that human-mediated movements of organisms outside their home ranges began to accelerate during Europe’s age of exploration and conquest in the 15th century and have continued to increase through the present.

The benefits of introduced non-indigenous organisms are legion. The utility of rubber trees, originally from the forests of South America, in raising our country’s economy cannot be denied and the same can be said for oil palms and cocoa. Of late, however, there is an international upsurge of concern that non-native species are invading our tropical ecosystems. This concern stems from an ecological standpoint that an area’s biological wealth can be threatened by alien invaders.

Once outside their native communities, non-native species may gain many competitive advantages over their native counterparts, due to the absence of natural enemies (predators, pests, competitors), physiological mechanisms that can suppress the growth of native species as well as the ability to acquire nutrients in poor soils. Although not all introduced species are invasive, those that are have become too successful in their new environment resulting in the impoverishment of native biological diversity.

The human-mediated spread of non-native plant species in settlement areas is normally through garden escapes and improper disposal of green agricultural wastes, increased transport, trades and tourism. Thus, we can expect that high levels of human dependence on non-native plant species for food, ornamentals and other non-food uses will increase the abundance and the number of non-native species in an area.

Then, there is the possibility that these species can be easily dispersed and propagated into more diverse but threatened habitats such as adjacent secondary forests and forest reserves. Identifying the various vectors, stages and pathways of introduction into these protected habitats is therefore important for effective mitigation and control policies. By far, agriculture is the main pathway of introduction because it is the most extensive land use surrounding secondary forests and forest reserves in this country.

Agriculture in Malaysia, as in many other developing countries in the tropics, can be divided into large-scale high-input monocrop plantations (rubber, oil palm, or rice) and low-input traditional cultivation which includes shifting cultivation by various indigenous groups. In each of these different agricultural “habitats” different non-native species can occur and thrive.

At the moment, data on the uses and cultivation of non-native species by indigenous communities living close to forest reserves in Malaysia is likely to be restricted to anecdotal notes or hidden in forest community surveys. There is information waiting to be gleaned from the dusty pages in the libraries in this country and overseas. But such efforts will be rewarded with sobering if not surprising results. In her own research, the author discovers that while it is commonly claimed that “our forests” are a native resource that provides everything to the people who live in or close to these forests, the list of forest species being consumed by the forest peoples in this country actually include non-native species originating from faraway regions. For example, John Wyatt-Smith, a British forester, commented around the time of Independence that shifting agriculture was a ‘primitive type of agricultural practice’ carried out by various ethnic groups (Malays, Siamese and Orang Asli) to plant tapioca, maize, sweet potatoes, bananas, padi huma and fruit trees. However, this list of crops shows more than half of the planted crops (sweet potatoes, maize, tapioca) are non-native species, introduced into the peninsula by foreign traders and colonialists. It also indicates that indigenous peoples are indeed adaptive to changing times.

In a recent study on the uses of non-native plants by Malay villagers in Negeri Sembilan, the author found that these villagers, who were living close to secondary forests, had been for several generations using non-native plant species for ‘traditional’ medicine and foodstuffs. While some of these plants were planted around the homegardens for household use, many non-native plants were common in the secondary forests and had long acquired local names. On the one hand, this incorporation of non-native species in the local traditional knowledge is anthropologically interesting because it demonstrates the resilience of indigenous peoples. On the other hand, it raises concern that the challenge to stop the spread of non-native species may be very difficult.

But it is hard to dispute the contention that to pave for an understanding of the pathways of introduction more studies on non-native plant dependence by various ethnic groups are needed. Such studies could include identifying the non-native plants being used or cultivated by different Orang Asli communities living relatively near forest reserves. Of course, the inventory should not be restricted to the useful non-native species but inclusive of all introduced species in the ladang and homegardens. This effort can be extended to include the aliens present in the adjacent forests.

Inventories are crucial. Information on the distribution of non-native species in this country is few and far between. Worse it has not been updated. The best references to date on non-native plant species in the Peninsular Malaysia are those researched and written many decades ago by I.H. Burkill, published in 1935, and M.R. Henderson, published in 1954, even if these early authors did not record the uses of each species by the people in this country. In light of the threats posed by alien species invasion, this is a pitiful state of ignorance and neglect.

Elsewhere in the world, the concern about non-native species invasion seems to be reflected in the efforts being put in their publicity. And, there is a multitude of information about invasive species in many countries, especially developed ones. Online databases of non-native plant species for other tropical regions e.g. the Pacific islands including Hawaii are available on the websites of Prospective Invasive Species for Pacific Islands (PIER) and Hawaiian Ecosystems at Risk Project (HEAR). These databases are also useful for Malaysian scientists and conservationists for comparison as well as acting as baseline data. Clearly, we need to match if not double the efforts made in other countries here in Malaysia with regards alien invasion if we are serious about conserving our biological diversity.