BBC News has this story about the invasion of beaver (Castor canadensis) on the Argentinian part of the island known as Tierra del Fuego. The beaver was introduced from Canada in the mid-1900s with the goal of creating a fur industry. Coincidentally, this is one of the same reasons a wetland rodent native to Argentina, the nutria (Myocastor coypus), was introduced to the southern U.S. Unfortunately, neither project was successful from a business standpoint. Now the beavers in Argentina are messing with loggers by claiming trees as their own, damming rivers, and polluting the water. Stakeholders are concerned about what could happen if the beavers make it to the mainland.
Thanks to a member of the ALIENS-L listserver for posting a link to this story.