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Published on: 4/28/2008
Last Visited: 4/28/2008
"The natural process happens over slow time periods," says Barry Rice, an invasive species specialist with The Nature Conservancy.
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"A really good analogy is to think about invasive species [as you would] wildfires," Rice says."You can control a small fire when all you have to do is step on it, but once it's a large blaze, the logistics are much more complicated."
The first line of defense, he says, is to take appropriate biosecurity measures whenever possible.For example, many of the sub-Antarctic islands have implemented simple procedures, such as requiring visitors to dip their shoes in biocide (a chemical that kills microbes and plants) before disembarking onto the islands to prevent seeds or new pathogens from being introduced.
But it is impossible to prevent all invasions, which is why Rice stresses the importance of a network of experts who can immediately identify new threats and nip them in the bud.The Invasive Plant Atlas of New England project is doing just that, using trained volunteers to inventory habitats and document the arrival and spread of invasive species.
Once intrusive populations become established, it can be almost impossible to get rid of them.Often, as is the case with rats, feral pigs and many plant species, they have extraordinarily high reproductive rates.
Rice says that efforts to control invasive species should be tailored to each situation.
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"If I'm a preserve manager and I decide to wipe out every nonnative species, I will drive myself crazy and break my budget," Rice says.
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"When we find ourselves in a situation [in which] we have to kill some organisms because we introduced them and they're damaging native organisms, ultimately this is a tragedy," Rice says."We should take responsibility for that tragedy and we should channel that energy into avoiding introducing such organisms in the future."
Still, he says, although problems associated with invasive species may be pervasive and complicated, they are not insurmountable.
"You can define successes on a regional level,they're not measured only by whether the organism has been eradicated," he says.