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Mark Shwartz, News Service (650) 723-9296; e-mail:

Passport, please: a global strategy to curb invasive species

Plants have no respect for boundaries. Nor, for that matter, do zebra mussels, crazy ants or Nile perch. When alien species invade, they wreak havoc on economies and ecosystems across the globe. Curbing the problem is an international task, says Harold A. Mooney, a Stanford biologist who helped design a global plan to deal with the invaders.

"If we have a fire, then we send for the fire truck. People respond right away. But we have no strategy for invasive species," says Mooney, the Paul S. Achilles Professor of Environmental Biology. He will outline a 10-point strategy to curb invasive species at the American Association for the Advancement of Science (AAAS) conference on Friday, Feb. 16, at 9 a.m. PT.

Mooney is speaking on behalf of the Global Invasive Species Programme (GISP), an international collaboration of scientists, lawyers and policy makers that has been working for three years to come up with an effective and globally acceptable plan.

Behind habitat destruction, alien invasion is the second greatest cause of species extinction worldwide. On islands, alien invasion is the number one cause of extinction, says Laurie Neville, project officer for GISP.

When the small brown tree snake arrived on the coast of Guam, it entered an island with 13 species of forest birds, 12 types of lizards and three bat species. Today, only one bat species remains, three forest birds and six native lizard species.

Biodiversity loss, though devastating, is not the only issue. More than one million nocturnal brown snakes now inhabit even the smallest spaces on Guam. They cause blackouts by crawling on power lines, hunt in family chicken coops and slide into homes through bathroom vents.

Guam may sound extreme, but many examples rival the plague-like status of the brown tree snake. The invasive, hardy water hyacinth strangled the ecosystem and economics of Lake Victoria in Africa until a multimillion-dollar international control program was put into effect. Crazy ants form supercolonies in the rainforests of Christmas Island, changing the habitat and preying on the animals of the forest floor. The alien star thistle outcompetes native desert grasses of California. "The rangelands of the west are being taken over by noxious weeds causing enormous financial loss," Mooney says.

The human propensity to travel -- carrying plants, animals and bacteria -- is essentially taking our ecosystems back some 200 million years, when the Earth's land masses consisted of a supercontinent called Pangea. During that era, plant seeds and animals could move freely across the land, since they were not yet separated by thousands of miles of ocean. Mooney dramatizes the long-term consequences of alien invasion by holding up a picture of the continents as Pangea once again.

Currently there is no global network set up to deal with or prevent future ecosystem invasions. "We're looking at designing something like the CDC [Centers for Disease Control]," says Mooney. "We need something comparable for invasive species." He will introduce the 10 elements of the GISP global strategy -- a "framework for mounting a global-scale response" -- at the AAAS symposium.

Mooney will describe the need for a "rapid response mechanism" a fire truck for invasive species. If nations develop the resources to react immediately to an invasion, they will save money and time by controlling the invasive species before it establishes itself.

Mooney also will address the crucial need for developing international financial checks and balances. "If you import something, and it gets away, you should help pay," Mooney says. He suggests adopting a type of bond, or insurance system, where those who do the importing contribute to a fund set aside to fight harmful invasive species. The GISP strategy also recommends considering the actual cost of invasives and incorporating that cost into a financial code of conduct for the importers.

One of the most controversial areas, Mooney says, is the legal arena. "There are a lot of holes and inconsistencies" in current national and international law touching invasive species, he notes. The goal is to create consistent laws, whether in the export country, the import country, or both, that help minimize the introduction of alien species.

To synthesize three years of research and finalize the 10-point global strategy, Mooney met with other biologists, along with economists, lawyers and policy makers from around the world in Cape Town, Republic of South Africa, this past September. "This is a consensus," Mooney says.

Whereas in the past, the invasive species issue has partitioned people in agriculture, shipping and government, "that meeting in South Africa was a coming together," notes Mooney. "It was a breath of fresh air."


By Louisa Dalton

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