When the wolf seeks refuge from man hunting during breeding period https://www.sciencedaily.com/releases/2016/07/160720105348.htm
"Wolves lower the risk of interacting with humans during the reproduction period -- when they are most vulnerable -- and adopt some similar behaviors in their areas, from Alaska to India and Afghanistan, according to a new study. " ‎- JustDuckie
"The authors found general patterns in the breeding areas of wolves. Having in mind the hunting history by men in Eurasia and North America, the scientific team states that in Europe and Asia wolves are sensitive to humans when selecting the areas where to take care of their babies and they usually go for the highest and abrupt areas in their territories. However, in North America, this sensitiveness is not the same and wolves use to choose valleys and softer relief areas." ‎- JustDuckie
"According to the expert José Vicente López-Bao, "one of the hypotheses we consider is that the different persecution history done in both continents can be a reason to explain the seen patterns. In Eurasia, persecution started with the appearance of farming and it got stronger gradually, while in North America they ended with the wolves in big areas some decades after colonization and with efficient means from the very first moment."" ‎- JustDuckie