Abstract :
From 2001 to 2005, 71 costume-reared juvenile Whooping Cranes Grus americana were led by
ultralight aircraft from Wisconsin to a winter release site on the west-central Gulf Coast of
Florida. A strategy was developed and implemented to maximize first winter survival while preventing
exposure to non-costumed humans and tame Sandhill Cranes, maximize social bonding
between males and females, promote safe roosting and wild behaviour, and minimize harassment
by Whooping Cranes from earlier releases. Methods were improved each year; these modifications
included enlargement of an open-topped release pen, creation of an artificial roosting
substrate, addition of a top-netted pen, and holding birds at a distant pen site until older birds
had cleared the release area. These techniques resulted in high survival and successful adaptation
to the wild after migration from the winter release site.