When you hear someone bubbling enthusiastically about an exotic species, you can safety bet the speaker isn’t an ecologist. This is a name for a resident of an established community that was deliberately or accidentally moved from its home range and became established elsewhere. Unlike most imports, which can’t take hold outside their home range, an exotic species permanently insinuates itself into a new community. Sometimes the additions are harmless and even have beneficial effects. More often, they make native species endangered species, which by definition are extremely vulnerable to extinction. Of all species on the rare or endangered lists or that recently became extinct, close to 70 percent owe their precarious existence or demise to displacement by exotic species.