It is found from Colorado north, Alaska, including from the Upper Cook Inlet region to the tundra.

The short Alaskan summers disrupts the parasitic life cycle preventing the spreading of diseases.

Black-capped chickadees (Poecile atricapillus) in Anchorage and Fairbanks were found to be infected with the malaria virus but none in Coldfoot.

This includes ponds, sloughs, fresh or salt water marshes, containers, hollow trees, low depressions of land especially such as tundra, and moist areas of fields, bogs, and forests.

In many northern regions, around winter breakup, there can be hordes of the large and vicious hibernators.