Whooping Cranes Learned to Migrate by Following Costumed Pilots

What a throwback. I haven't thought about the movie Fly Away Home since I was a child. Really awesome to see people caring enough about animals to do stuff like this.

https://en.wikipedia.org/wiki/Fly_Away_Home

With a population bottleneck of only 21 individuals, it sounds like their entire population is inbred. Even if it's hundreds of individuals now.