Environmental
biologists use the term extirpate to describe
species once
endemic but now locally
extinct. For example, the loggerhead
shrike is in danger of extirpation in
Ontario, but not in danger of species
extinction.
For a species to be extirpated, it has to be extinct within a species-significant range. You can't say that pigeons have been extirpated in your backyard because they no longer visit it. In the example of the loggerhead shrike it is believed that the endangered birds are a complete subspecies, and that they are in danger of extirpation throughout the range of the subspecies. Loggerhead shrikes are relatively populous in other regions.