Subsequent range expansion of introduced species may or may not involve human activity.

This range expansion may be due to the warming of the surface waters.

They may also wander north in late summer after the breeding season, which may have assisted its current range expansion.

It may be difficult to determine range expansion, though, because of its small population sizes in certain areas, including central Oklahoma.

White-eye range expansion has also been cited as a negative effect on native bird species.

Moisture of soil or air is also seen to limit range expansion.

It also has a recent range expansion into Western parts of Uganda.

The range expansion increased the size of their territory by 22.3 percent.

More evidence is required to tease out the particular forces that drive this type of range expansion.

Its range expansion has not been aided by human introduction.