Results of the first ultralight-led sandhill crane migration in eastern North America

Abstract

In 1997, we led 8 sandhill cranes (Grus canadensis) south from Ontario, Canada by ultralight aircraft to a wintering area near Warrenton, Virginia, an area without a wild population. Six others were transported south in a trailer in hopes they would return north with those that flew. The migration was 863 km long, included 14 stops, and took 21 days to complete. All 13 surviving birds were wintered together. In March 1998, the surviving 7 'aircraft-led' birds departed the wintering site. The following day, 6 of the 7 were reported on the south shore of Lake Ontario. The flock then moved around the western tip of Lake Ontario. On 5 April 1998, we used 2 aircraft to lead the birds 104 km directly east to the rearing area. The flock soon moved off the fledging grounds, continued to associate with people, and was eventually removed from the flyway. Because no wild cranes are known to fly our chosen route, this study demonstrated not only the effectiveness of ultralight aircraft to lead cranes on migration, but it also proved that cranes so led can return from their wintering site to the general vicinity of their fledging area unassisted. The birds did not follow our indirect route south but rather flew north to the latitude of the fledging area, then wandered.