They are not aliens from another planet, or foreign spies from another country. Although many of these invasive species are causing harm, the harm they are causing is due to them trying to survive. If a species is brought to a foreign land, it will do whatever it can to thrive in its environment. If that means it takes advantage of pre-existing native species, it will do that. Most of these species have been brought here by humans, they did not choose to invade us. Also, most of these invasive species are being killed. Sure, the death of one invasive species to save a whole population is reasonable. But, a bias has been formed around invasive species. People are judging a species' danger by its origin. That should not be happening, a species' danger should be determined by its impact on the environment, not where it is from, and invasive species should not be blamed for all of the destruction of the environment (Davis 153–154). The treatment, equality, prevention, management , and extermination of invasive species is not right.
There is a bias surrounding invasive species, even the definition is biased. The official definition of an invasive species, according to the National Invasive Species Center, or NISIC, is a "non-native (or alien), to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm to human health" (What Is an invasive species" (28 Nov 2012). Even the official definition of invasive species does not include the possibility of an invasive species being helpful to the environment or not affecting it in a totally negative way. This is biased because there is research that shows examples of invasive species not harming their environments. It is true that there are invasive species that greatly harm their environments, but all points of view should be looked at in an official definition. Because the definition is biased, so is the opinion of the public.