EARLY EXPERIENCE AND DEVELOPMENT OF FOLLOWING BEHAVIOUR IN TRUMPETER SWAN (CYGNUS BUCCINATOR) CYGNETS

Wayne Bezner Kerr
University of Guelph, 2000

Induced migration behind aircraft has been proposed as a technique to conserve and restore some bird species, but success has been variable. To investigate whether and how early experience affected the development of ability to follow aircraft, 4 groups of trumpeter swan (Cygnus buccinator) cygnets were raised under 4 different combinations of hatching and rearing conditions, ranging from minimal human contact to a fully manipulated regimen in which cygnets were incubator-hatched and reared by human handlers. One group of hand-reared and one group of initially parent-reared cygnets were trained to follow an ultralight aircraft after 10 d post-hatch. One of group of hand-reared and one group of initially parent-reared cygnets were isolated from human contact after 10 d post-hatch. All cygnet groups were subsequently tested for ability to follow aircraft. Cygnet association with human handlers and the research aircraft, time-activity budget data and tendency for cygnets to takeoff with the aircraft were recorded. Between 10 d and 80 d post-hatch, initially parent-reared cygnets demonstrated significantly lower preference for human handlers and the aircraft compared to initially hand-reared cygnets, but eventually followed the aircraft better in flight than initially hand-reared cygnets after 90 d post-hatch. The group of initially parent-reared cygnets was the only group in which following behaviour was sufficiently developed that they could be led by aircraft on a 1250 km migration.