All it takes is for some of them to get spooked (one of the reasons I hate fireworks), and they're gone forever.
Along the same lines, this is also sometimes the fate of people who get lost in the wilderness. All those YouTUbe videos about lost people in national parks and wilderness areas. I'll guarantee you, 98% of them became lost and fell off cliffs, drowned in rivers, or died of exposure. I once encountered a guy just 100 yards off the main trail on a secondary trail, and he was already lost, asking me for help. Most people can get lost within seconds without direction.