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Invasive Species and Poverty The missing Link... I nvasive alien species are now recognized as a great threat to biodiversity. They also constitute a threat to the environmental and economic well-being of our planet, costing an estimated $1.4 trillion per year, or nearly 5 percent of global GDP (Pimentel and others 2001). Invasive species are not a new phenomenon. Farmers have been fighting weeds since the beginning of agriculture, and throughout history epidemics of human diseases—such as malaria, yellow fever, and bubonic plague—have been recorded. Yet in the 50 years since Elton first coined the term, the issue has assumed large proportions. Invasive species are plants, animals, or microorganisms whose accidental or intentional introduction into a new ecosystem threaten biodiversity, food security, human health, trade, transport, or economic development. What is of most concern is the rate at which invasive species are being introduced, coupled with increases in their distribution as a result of globalization, in particular increasing tourism, travel, transport, and trade. Emerging conflicts with commercial interests promoting the utilization of potentially invasive species, such as those used in biofuel production, are further confounding efforts to combat the problem. Moreover, the threat of climate change will favor species that are adaptable or opportunistic, a characteristic of many invaders. Climate change will inevitably exacerbate this problem, with consequences for biodiversity and human livelihoods. Invasive species occur in all taxa and affect virtually all ecosystem types. They were identified by the Millennium Ecosystem 12 Dr. Dennis Rangi Chair Global Invasive Species Programme Assessment as one of the main drivers of biodiversity loss and changes in ecosystem services. Invasive species are responsible for 33 percent of threatened birds (but up to 67 percent on islands), 26 percent of threatened amphibians, and 16 percent of threatened mammals. Their status as the second biggest threat to biodiversity—and in many ecosystems, such as small-island developing states, the biggest single threat to biodiversity—has been well documented and is well deserved. The links between invasive species and poverty, specifically food security, continue to be poorly understood and frequently underestimated. In most countries, invasive species are viewed exclusively as a biodiversity issue and thereby confined to the mandate of the environment sector—traditionally not a priority for developing country governments. As a consequence, the threat posed by invasive species to food security and poverty alleviation has not been given adequate recognition by policy makers. In developing countries—where agriculture accounts for a higher proportion of GDP, many ecosystems are fragile, and infrastructure is often weak—the negative impacts of invasive species on food security and economic development could cost as much as 20 percent of GDP. Food security is highly dependent on the adequate production of staple foods, yet this is precisely where the impacts of invasives species are most acute. For example, the larger grain borer costs Tanzania $91 million in lost maize production, while soybean rust costs Brazil $1 billion annually. More than half the staple crops planted in developing countries are rou- Environment Matters 2009 • THE WORLD BANK GROUP VIEWPOINTs tinely destroyed by invasive species, pre- and post-harvest. Data for just eight staple food crops indicate that these yield losses cost $12.8 billion per year. If maize stemborers could be controlled in the maize-producing countries of eastern and southern Africa, enough maize would be saved to feed another 27 million people. If we are to address Millennium Development Goal 1—to halve hunger and poverty by 2015—then we must recognize the threat of invasive species. and 1970s as a “miracle tree,” used primarily for firewood. In many parts of Africa, the tree has since become invasive, threatening biodiversity and food security. Commercial farms currently spend considerable sums of money trying to control Prosopis, uprooting them with bulldozers and burning Prosopis trees found on farmland, roadsides, and irrigation and drainage canals. In severe cases, farmers in Ethiopia have been forced to abandon their farms and livelihoods as a direct result of P. juliflora. Trade is a conduit for introducing invasive species. As the levels of import and export trade increase, so does the risk. For example, shipping is a major pathway for the unintentional introduction of aquatic invaders, carried in ballast water and/or as fouling organisms on the hulls of vessels. There are 6 million containers on the High Seas currently, and it is estimated that the global shipping industry will more than double by 2020. Other pathways of importance include civil aviation, aquaculture, and the pet trade. To a great degree, we have the knowledge and the technology to prevent, control, or manage most invasive species, thereby avoiding adverse consequences. What appears to be lacking is an awareness of the multisectoral nature of the threat, an international framework for addressing invasive species, and the political wherewithal to take the immediate action necessary to remove this particular barrier to food security and poverty alleviation. Even international assistance programs are not immune to the impacts of invasive species. In 2001, as millions of people in Africa were facing starvation due to droughts and floods, the food aid shipments also acted as pathways for invasive species. For example, Parthenium seeds entered Africa as “hitchhikers” and subsequently invaded surrounding ecosystems, causing irreversible damage. Parthenium competes with native and useful introduced plants; causes allergenic reactions and skin irritation; contaminates seed, grain, and hay; and is toxic to animals. To achieve poverty alleviation, we must begin by removing invasive species as one of the main barriers. Other species are introduced legally but without an understanding of their potential risk. An example is the agroforestry species Prosopis juliflora, which was introduced into Africa in the 1960s The Global Invasive Species Programme (GISP) was established following the recommendations of the first international meeting on invasive species held in Trondheim, Norway, in 1996. GISP is an international, not-for-profit partnership dedicated to tackling the global threats of invasive species through policy development, awareness-raising, and information exchange. GISP’s mission is to conserve biodiversity and sustain human livelihoods by minimizing the spread and impact of invasive species. GISP’s goal is that by 2020, a majority of countries will have the necessary policies in place to implement their biosecurity strategies and action plans. GISP’s Secretariat—located in Nairobi, Kenya, with offices in Washington, D.C.—is responsible for coordinating GISP’s activities globally and facilitating implementation of the global strategy on invasive species. For further information, please visit the GISP website, www.gisp.org. Shutterstock Images LLC Reference Pimentel, D., S. McNair, J. Janecka, J. Wightman, C. Simmonds, C. O’Connell, E.Wong, L. Russel, J. Zern, T. Aquino, and T. Tsomondo. 2001. “Economic and Environmental Threats of Alien Plant, Animal, and Microbe Invasions.” Agriculture, Ecosystems and Environment 84: 1–20. GISP is an international association of four founding partners, namely CABI, the International Union for Conservation of Nature, The Nature Conservancy, and the South African National Biodiversity Institute. Dr. Dennis Rangi Chair, Global Invasive Species Programme GISP Secretariat, United Nations Avenue, P.O. Box 633-00621, Nairobi, Kenya www.gisp.org annual review • July 2008–June 2009 (FY09) 13