I'm doing a family tree and I've hit a wall. I've noticed some surnames change depending on location and father's first name in Norway.

ei: Sven Johan = father of Ivan Svensen = father of Ludvig Ivansen = father of Helen Ludvigdatter

Their lastnames sometimes take the fathers first name plus "sen" (son) or "datter" (daughter). They even add the town they come from sometimes.

ei. Sven Ivansen Bergen, Sven Ivansen Barstad

This is my problem. I have traced my ancestor Tollef Barstad (41), wife Bertha Barstad (39, who's maiden name may have been Young), sons Eyvind (12), Olaf B. (9), Terje (3) and daughter Borghild (7) to arriving in Halifax, Nova Scotia, Canada on April 30, 1927.

When I try to search to find them in Norway, I come up empty. I don't know if they changed their lastname when they came to Canada to reflect their town or what. I'm at a loss. My family tree has been put on hold until I can get more info.

Anything anyone can offer to help me, would be appreciated.

Thankyou