One more thing...You will find the name spelled different ways over the generations so be open minded. Here's one form I saw today - Kråkenæs which would also be Kraakenaes. There is at least one other farm that is spelled similarly but from a whole different area of Norway.
The farm names were not surnames in Norway but rather an address. Later the farm names may have been adopted as a surname when it was required to adopt a surname. You may find others who used the address/name but were not related to Mons - they just happened to live on the same farm. There was often more than one household on a farm - little subfarms under the larger farm. Confusing?
It is odd that I don't find him emigrating through Bergen on the online databases or on a list of emigrants that I have.