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Invasive Species Resources

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Scientific American.
In 1946 the Argentine Navy imported 10 beaver couples from Canada and set them free in Isla Grande, the deep south of Tierra del Fuego, with the intention of "enriching" the native fauna—and the local fur industry. The consequences of such initiative were disastrous: Protected from hunting for 35 years, and devoid of natural predators, the beavers grew over 5,000 times their initial population, caused irreversible changes in the forest ecosystem, and started advancing over the continent. Now, a study published in Chilean Natural History suggests that the demographic explosion of those beavers could be bigger than suspected because it can take years or even decades for local inhabitants to notice the rodents' presence and their impact on the surrounding ecosystems.