Invasive/Introduced organisms in a very localized place

The Dancing Kiss Fly and European Goldfinch are locally introduced in the greater Chicago area.

As far as plants are concerned (as generally slow spreading organisms), depending on the definition of “invasive species”, an alien species could be invasive though restricted in a very small area. In particular if the definition used is based solely on the impacts at the ecological level.
For me it should be better to separate the ability of spreading on a large area from that of making ecological impacts so that a certain species can be both naturalized and impacting (that is still not able to spread vastly but still able to exert ecological impacts)