Biological Pollution - Plants
& Bugs Popping Up
Where They Don't Belong
WASHINGTON (AP) -- An alarming breed of biological pollution, spreading around the world, may be sitting quite prettily in your backyard.
Exotic species of plants, bugs and animals, carried across borders intentionally or by accident, are posing new dangers in places they don't belong.
Termites from Taiwan are eating American houses while an Atlantic jelly fish is destroying fisheries in the Black Sea. The South American water hyacinth is shrouding lakes in China and Africa, while tree snakes from Papua New Guinea are gobbling up bird species on the faraway island of Guam.
Like global commerce, species are travelling faster and further than ever.
They swim in the ballast of supertankers, slither up into the wheelwells of jetliners, and sometimes, bore into valuable artifacts.
Environmentalists call it "smart pollution," because new species can quickly evolve to dominate and sometimes destroy native plants and animals.
Environmental researcher Chris Bright says its the second greatest threat to the biological diversity of the planet, next to the loss of habitat.
"Even the worst chemical spills are dumb. They cannot reproduce and they dissipate over time. But smart pollution proliferates and spreads," said Bright, author of Life Out Of Bounds, published this weekend by the non-profit environmental research group Worldwatch Institute and W.W. Norton and Co.
"Invasion itself is an ancient process," said Bright. "What's new is that the integration of the global economy is spreading more and more creatures around.
Some invaders are well known: the pipe-clogging zebra mussel, the bird-devouring brown tree snake or the landscape-smothering kudzu vine. Most are more subtle and can be found in backyard gardens or public parks.
"We can look right at it. It can be looking us back in the face and we don't even see it," Bright said.
About half of the 300 serious plant pests in North America were first grown in gardens, says the report.
Some are still being sold in nurseries, including purple loosestrife, which Bright said first came to North America in the 18th century, probably with seeds hiding in wool imports.
It has now overrun more than 150,000 hectares of wetlands, strangling out native vegetation and ruining waterfowl foraging areas.
Other foreign invaders of various lands and waters include:
--Rubber vine from Madagascar that now infests large swaths of Queensland, Australia, smothering trees up to 30 metres high.
--The Asian tiger mosquito, which can carry at least 17 different viruses, some of them fatal, and has turned up in such scattered places as Brazil, Nigeria and, last fall, in Peoria, Ill.
--The possum, a nocturnal marsupial from Australia, that has moved over to New Zealand, multiplied, and now chews up an estimated 20 tonnes of native bark, buds and leaves every night.
Bright said that "attempts to deal with the problem in an integrated way have been pretty weak and inconsistent."
Future dangers also lurk.
The book warns of the danger of yellow fever travelling from Kenya to India, where the population "is wholly unvaccinated against it."
It also cites the potential danger of Amazonian rubber pathogens migrating to Southeast Asia where they could destroy most of the world's rubber production.
The report suggests strengthening international treaties, re-engineering ship ballast water systems that carry foreign plants and creatures, developing international monitoring systems on invasive species, stopping the intentional introduction of exotic species and promoting the use of native species in gardens around the world.