For a wealthy society with strong shipping connections, this is difficult but possible.

For a shrinking society with fewer ships and fewer people, it becomes progressively harder.

The economic foundation could therefore erode even if the farms themselves still looked viable.

This may help explain why the Norse did not necessarily disappear because they could no longer survive in Greenland at all.

They may have disappeared because maintaining their particular European-style society there stopped making economic sense.

Walrus hunting was therefore both an opportunity and a risk.