Only a handful of immigrant wolves reach Swedish breeding grounds amid high mortality

The 25-year Skandulv wolf-tracking study has documented 44 wolves entering Sweden from Finland and Russia since 2010, a vital boost for a highly inbred Scandinavian population. However, only eleven of those migrants reached the southern breeding districts; thirteen were legally culled in reindeer-herding zones, and others fell victim to traffic accidents, illegal poaching, disease, starvation or elk attacks. Project leader Håkan Sand notes that most losses occur among young, inexperienced wanderers.

Among the survivors, seven managed to sire litters, and the progeny of four of those wolves have already produced their own pups. Relocation efforts involving sedation and transport to southern habitats have sometimes succeeded but often fail when the wolves migrate back northward, reflecting their strong territorial instincts.