i suspect beavers in the amazon will likely be invasive, as they dont have natural predators other than probably anacondas? maybe jaguars, or other wildcats, but they mostly are in water. and they can bring diseases, and parasites to the amazon. one thing rodents are good is at, is breeding large numbers, but beavers might be different. the Nutria looks like a beaver with a tail has become invasive in N america.