What's the difference between "invasive" and "nuisance"?
"Invasive" species come from other watersheds, other regions, or other continents. In a new landscape, they may have no natural controls, such as predators. As a result, nonnative animals, such as feral hogs, often eat local wildlife or their foods and consume or destroy their habitat. Invasive plants, such as spotted knapweed, can also outcompete crops and livestock forage, reducing economic productivity.
"Nuisance" animals are native to the local landscape but can still cause problems. Canada geese, for example, have historically used Missouri for summer breeding grounds, but they have become nuisances where they have year-round access to short, palatable grass and open water. Raccoons can be troublesome when they repeatedly knock over trash cans or get into your chicken coop.