Marlyss Simmons put me onto a story on NPR about using ultralight aircraft to teach whooping cranes to migrate. This has been successful in increasing the Eastern US population from zero to 100 over 9 years. You can read or listen to the story at this NPR site.
While you are at it, you might check out the story of how song bird migration is being traced using a tiny transmitter attached to the birds back. Apparently it only transmits and doesn't serve as a GPS or sattelite radio (yet). Go to this site.