
Given the following passage

"It has been possible to teach a migration route to a flock of birds, for example in re-introduction schemes. After a trial with Canada geese Branta canadensis, microlight aircraft were used in the US to teach safe migration routes to reintroduced whooping cranes Grus americana.",

answer the following question. Note that the answer is present within the text.

Question: The way that cranes had was described as thankfully taught by who? 

US
