Geology topics

Joseph W. Duff

Publications and source records attributed to Joseph W. Duff.

4 recordsLinked to original sources

USGS2003

Motorized migrations: The future or mere fantasy?

In 15 experiments from 1993-2002, we led cranes, geese, or swans on their first southward migration with either ultralight aircraft or vehicles on the ground. These experiments reveal that large birds can be readily trained to follow and most will return north (and south) in subsequent migrations unassisted. These techniques can now be used to teach birds new (or forgotten) migration paths. Although we are constantly improving our training techniques, we now have an operational program that can be broadly applied to those species where juveniles learn migration routes from their parents.

Arizona, Florida, Idaho, Indiana, Maryland, New Me↗

USGS2001

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

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.

Book chapter↗

USGS2001

Promoting wildness in sandhill cranes conditioned to follow an ultralight aircraft

During the 1998 field season, we developed and tested a new protocol to teach sandhill cranes (Grus canadensis) to follow ultralight aircraft yet avoid humans. Although successful in teaching the cranes a migration route, our previous migration (1997) resulted in birds that were overly tame and sought association with humans. For this study, 16 sandhill cranes were costume-reared at USGS Patuxent Wildlife Research Center and transported to Ontario shortly before fledging. After the birds learned to follow the aircraft, 14 were transported to an isolated wintering site in South Carolina, 1300 km south of the training area. Twelve arrived safely. Eleven of 12 birds survived the winter. All of these 11 cranes moved north to Cape Hatteras in early May. Thereafter, 6 of the cranes were captured and translocated to northern New York state. The remaining 5 returned to South Carolina, autumn 1999. Prior to capture, although the cranes sometimes allowed humans to approach them, none of the cranes approached buildings or humans.

Book chapter↗

USGS2001

Lessons from the motorized migrations

Ten experiments have been conducted to determine if cranes can be led on migration and if those so trained will repeat migrations on their own. Results have been mixed as we have experienced the mishaps common to pilot studies. Nevertheless, we have learned many valuable lessons. Chief among these are that cranes can be led long distances behind motorized craft (air and ground), and those led over most or the entire route will return north come spring and south in fall to and from the general area of training. However, they will follow their own route. Groups transported south and flown at intervals along the route will migrate but often miss target termini. If certain protocol restrictions are followed, it is possible to make the trained cranes wild, however, the most practical way of so doing is to introduce them into a flock of wild cranes. We project that it is possible to create or restore wild migratory flocks of cranes by first leading small groups from chosen northern to southern termini.

Book chapter↗