You might think that winter is the most dangerous time of the year for a young animal. But for Scandinavian brown bear cubs, these next few weeks may determine whether the animal lives or dies.

That’s because early May to mid-July is breeding season for Sweden’s brown bears. The males, in a desperate attempt to pass on their DNA, try to mate with every female they come across. This is especially dangerous for females with cubs, because a mother bear cannot become pregnant while she’s still nursing last year’s litter. That’s why male bears will sometimes kill the cubs, forcing the female’s body to stop lactating and shift back into reproduction mode.

But according to a study published Tuesday in the Proceedings