Door County is abuzz around Labor Day with monarch butterfly tagging events. In the fall, monarchs migrate from across America and southern Canada back to Mexico where they spend the winter. It's a journey of over 2,000 miles in some cases. So what exactly happens to the butterflies who are tagged? A group called Monarch Watch organizes observers south of the border to help identify tags. Naturalist Karen Newbern says many make it because monarchs are not exactly a delicacy.

Still, migrating monarchs have to deal with bad weather and exhaustion. Both of those factors can prove lethal.