There are two races or sub-species of the Pacific Wren. Although, which is usually the case, races are seen or found in the same type of habitat. This is not the case with the Pacific Wren. The Pacific Wren (Aleutian) is found on the open and barren landscapes of the Aleutian Islands and on the Pribilof Islands, which are both situated in the Bering Sea. It is usually found in the rocky outcropping along the coast. This is a large wren and is the largest in its group and it does not migrate. Then, there is the Pacific Wren (Pacific), that is seen along the southern regions of Alaska, southward and right into the southern regions of California. This race is seen mostly in the forests and it is usually observed on the forest floors. It may move into the interiors during the winter months.
The Pacific Wren was once part of the Winter Wren group. Now it is its own species with sub-species within its group. In general, but it is not always the case, it is seen on the western side of the Rocky Mountains. It moves further into the British Columbia rockies in breeding season.
Avibase - the world bird database This site provides the user with a complete list of bird species, broken down per country, or in the example of the US or Canada, per state and province. Here, bird species names are available in other languages, a great asset to be used as a translation of foreign bird names.
ABA - American Birding Association This site represents an organization that maintains official records of all birds species that have been proven to have been seen inside the perimeters of the North American Continent and the surrounding bodies of water. Regular revised versions are posted to keep the bird list current at all times. This is the list used by all serious birders over their lifetime. You may be aware of the movie called the "Big Year". It was with this list that all the competing birders used in an attempt to set a new record as to how many bird species that could be seen by an individual birder in one calendar year.
I hope you will take advantage of these suggested websites. I have used each of them, in one way or another, throughout the years in my quest to better identify and understand our fine feathered friends.