There are two types of siskins seen in North America. The Pine Siskin is the only native bird and is found throughout North America, where pine and spruce cones are available. The Eurasian Siskin is a common bird throughout Eurasia and has been seen on the North American continent and is more likely observed on the mainland of Alaska, the islands in the North Bering Sea or on the Aleutian islands chain.
In the winter months, siskins travel in flocks and behave like nomads. If birdfeeders are available, it is not uncommon for them to stay the whole winter. They have been known to stay and even make their nests and raise their young wih help from the feeders.
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.