In 1946, the Argentine Navy, far from the most intelligent military outfit you’ve ever heard of, got a bright idea. They would bring in some Canadian beavers, set them loose in Tierra del Fuego, and then the local folk would profit off of selling their fur. Tierra del Fuego, at the very tip of South America, is an island inhabited then by only a few people, mostly natives who would love to rake in the fortunes possible in the fur trade. What could go wrong?
Well, let me count the ways. First of all, the beaver fur trade has not been a big deal since the mid-19th Century. Canadians know all this but let me spell it out for the non-Canucks. Beaver fur was turned into excellent felt used to make hats. Once the European beaver had supplied the trade but they were hunted close to extinction. When Europeans discovered Canadian beavers — much larger and furrier than their Euro-cousins, they said, “Sacré bleu!” and “We’re gonna be rich rich rich!” depending on their mother tongue. Oh, and did I mention that they had plenty of natives willing to do the grunt work in exchange for pots and pans, crummy muskets, blankets, and rum. And some non-native people did get rich until, quite suddenly, people stopped wearing felted fur hats and switched to silk hats (if they were upscale) or felted wool or cotton (if they were otherwise). Beaver stopped being a valuable commodity, the Hudson’s Bay Company turned over its territory to Canada, who changed it into Manitoba, and… You get the idea: there is no large-scale market for beaver fur.
Second, the native Tierra del Fuegans weren’t particularly interested in hunting beaver, there being no pots, pans, muskets, blankets, or rum on offer for them, so they ignored the furry beasties. Which was probably just as well since no one from the Argentine Navy had bothered to clear the project with whatever ministry was in charge of wildlife and it wasn’t really legal to hunt them until 1981. Nowadays the bulk of Tierra del Fuego’s population is comprised of urban refugees from Buenos Aires, many of whom think the beaver are really cute.
Third, the beavers set about doing what beavers do, chewing down trees (man, do they love them some Argentine varieties — much tastier than willow or birch or aspen or any of those uninteresting Canadian trees) and reproducing. Beaver are rodents and they reproduce rapidly. A beaver pair will have two kits a year that will stay with Mom and Dad for another year while two siblings are born, then the young beaver go out and settle their own territory. The original imported 25 beaver pairs have now more than 200,000 descendants.[YouTube link]
Oh, and they can swim. So the fact that they are on an island doesn’t matter a whole lot. They crossed the Strait of Magellan at least as early as 1994. Now the beaver have spread into south Argentina and neighboring Chile.
But Wait! you say: Aren’t beaver good for the environment? Like in Three Against the Wilderness where a family repopulates B.C.’s Chilcotin region and helps stave off drought and floods and stuff. But that was in Canada, where beaver are part of an established eco-system. They gnaw down trees, build dams, hold water in ponds that eventually become bogs and meadows and then forest again. All kinds of flora and fauna are just ready and willing to occupy that space at each and every stage of its development. But Tierra del Fuego isn’t British Columbia. Native trees are not adapted to beaver-kill, unlike North American varieties that can regrow from the roots. So the forests there are disappearing into beaver-made bogs faster than the environment can cope. Sure, give the place a few centuries and there’ll be a sort of balance achieved, the same way that, if you allow Europe or the Mid-East a few centuries of untrammeled murder and ethnic cleansing, neighborly communities will arise.
Did I mention that southern Chile and Argentine Patagonia are really lush territory? At least now, before they get beavered.
This problem has raised diplomacy between Chile and Argentine to new heights and these nations have agreed on a massive beaver hunt. They will cooperate in slaughtering every single one of these lovable animals that exist. It will take eight or nine years and involve helicopter gunships wasting every beaver lodge they find. No doubt this plan was developed after studying American success in eliminating communism in S.E. Asia or perhaps it’s based on the Soviet triumph in Afghanistan. I think Australia tried something similar when they were overrun by rabbits with minimal success. Now Australia has that big “rabbit-proof” fence that stretches for miles across the outback — sort of like the wall between Israel and Palestine or the one between China and Mongolia — that is supposed to keep the unwanted species out. Anyway, there is serious doubt that the South American beaver can be exterminated. Sooner or later, someone is going to suggest biological warfare, some kind of toxin or anti-reproductive substance that will target only beaver. There’s been a lot of that kind of thing over the years, aimed mostly at insects but sometimes at rodents. I don’t think that either mosquitoes or cockroaches show much population loss, though. And, of course, you can always introduce some species that will attack beavers. Something big and nasty and hungry with fangs and sharp claws, something that won’t bother human beings at all. No.
The single best on-line source for this that I have found is JonsAdventure. This entry is cited above several times. There is a good map of beaver expansion, too.