Arctic fox walks 3,500 km from Norway to Canada
theguardian.com
theguardian.com
Svalbard is a smidgen less than 1000km north of mainland Norway.
I don't believe that the Arctic sea ice has reached the mainland in my lifetime and I'm not sure how far back you'd need to go.
Svalbard is Norway in the sense that Hawaii is the US. It's true, but the journey is completely different.
It's not too surprising to me that a fox would use the sea ice for transport - it would surprise me to learn that foxes could swim from northern Norway to Svalbard.