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Warmer World Equals More Pests

Beetles killing trees in North America, bluetongue disease ravaging livestock in Europe, and borers destroying African coffee crops are examples of migrating invasive species not getting enough attention at global climate talks, scientists said Dec. 8.

Invasive pests have plagued agriculture and nature for thousands of years as mankind’s migrations brought them to places without natural enemies. But the price tag to battle them, now estimated at $1.4 trillion annually, may go up as rising temperatures and more storms and floods unleash species to new areas.

“The problem of invasive species has been all but omitted from the UN talks here in Mexico,” A.G. Kawamura, the secretary of California’s Department of Food and Agriculture, told Reuters.

He said scientists want to reintroduce the issue of invasive

insects, germs and plants so at next year’s talks in Durban, South Africa, pests will be a top subject.

Humans are also at risk as mosquitoes and other pests may spread malaria, dengue fever and other diseases as they move north. Nobody can say a particular outbreak is caused by climate change, but a look at growing problems in ecosystems can give clues to what the world may face if the world warms further.

Pine beetles are probably North America’s worst example of a pest broadening its range and causing damage. The hungry bug, facing no predators, has moved north into Wyoming and Canada, costing billions of dollars in lumber and land values as milder winters fail to kill it.

As pests transform forests and other ecosystems, their regions to store carbon dioxide in plants may also be affected, and hurt the world’s chances to fight climate change.


And it is not just higher temperatures from climate change that link pests to damage. James Maclachlan, a pathologist at the University of California, Davis, said outbreaks of bluetongue disease in European sheep and cattle may be the “point of the spear in the global emergence of viruses driven by climate change.”

Bluetongue, which is transferred to livestock by biting midges has caused hundreds of millions, if not billions, of dollars’ worth of damage to European agriculture, Maclachlan said on the sidelines of the climate talks.

The infected midges, which originated in the Middle East and North Africa, are carried to other regions by dust storms, which are expected to get stronger from climate change. The infected bugs spread the disease to local midge populations that have infected livestock as far north as Norway.

The disease affects milk production in animals and can cause trade disputes. France has had to curtail livestock trade to Italy because of the disease.

Dead forests:The pine beetle has cost billions of dollars in lumber and land values as milder winters fail to kill it.


Theproblemof invasivespecieshas beenallbutomitted fromtheUNtalks hereinMexico.”

– A.G. Kawamura, Secretary Of California’s Department Of Food And Agriculture

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