One reason for this could be the intense hunting in Sweden, which has created a population of elks which prefer to run rather than fight. That may keep them away from slow humans but it’s not much of a defence against nippy wolves.
Håkan Sand, a researcher in a Scandinavian wolf preservation project called “Skandulv”, told Swedish Radio that Swedish wolves kill one elk for every two attempts to hunt them. In North America, on the other hand, it seems that packs of wolves on elk hunts only manage a kill on 15% of hunts.
“The question remains as to whether Swedish wolves are better hunters than the North American wolves”, said Sand.
This, however, has proved not to be the case and it seems that American elks are simply more aggressive. Elk cows that have a calf in their tow are particularly tough, confirmed Swedish Radio.
“They defend themselves against the wolves with fatal kicks in very fierce attacks”.