Download invasive species and poverty

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
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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.
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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)
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