North American Crane Working Group


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Olson, G.H., and J.B. French. Behavior comparisons of two rearing protocols for whooping cranes raised by costumed caregivers and trained for an ultralight-led migration. In: Hartup, Barry K., ed., Proceedings of the Eleventh North American Crane Workshop, Sep 23-27, 2008, Wisconsin Dells, Wisconsin (Baraboo, WI: North American Crane Working Group, 2010), p. 211.


Reproduced by permission of the North American Crane Working Group.


Whooping crane (Grus americana) colts are raised at USGS Patuxent Wildlife Research Center, Laurel, Maryland for the first 40-60 days of a chick's life as part of the Whooping Crane Eastern Partnership (WCEP) ultralight-led reintroduction. Numbers raised for WCEP are increasing each year. Up to 2005, we raised whooping crane chicks in the Propagation Building where there are 10 indoor/outdoor pens, 8 full pens, and 2 half-size pens. In 2005 WCEP proposed increasing the number of colts reared to 20-24, numbers beyond the capacity of the facility. To accommodate this greater number of chicks, we modified several outdoor pens nearby. Pens were made smaller, protective lower fencing was added, and heat lamps were installed in the feed sheds. The addition of 6 such pens allowed rearing and training of 22 chicks. Chicks were placed in these outdoor pens at 25-30 days of age. The purpose of this study is to measure the effects on chick development and training from the new rearing procedure. Our training program is as follows: for the first week colts need to master the arts of walking, eating, and drinking, and this is the time of the most intense contact with costumed caregivers. Late in week 1 (day 5.8 ± 1.4 days) the colts are taken for foraging trips with a costumed person. Colts are taken to forage near the ultralight trike to become conditioned to the machine and the long crane head puppet at a mean age of 7.5 days ± 2.0 days. The next step in conditioning the colt is to begin circle training with the ultralight. Also in week 2, swimming to increase exercise and prevent leg deformities begins, as well as socialization with other colts, initiated at a mean age of 10.9 days ± 2.8 days. Exposure to water, also referred to as pond training, begins in week 2 at a mean age of 8.9 days ± 2.6 days. During week 3 circle pen training continues up to an average age of 30.8 days ± 3.9 days. Colts receive an average of 3 hours, 13 minutes ± 44 minutes of circle pen training. In week 3 the colts graduate to open field training. In 2005, colts received an average of 112 minutes ± 64 minutes of open pen training. This training started at day 31.9 ± 3.4 days. Average age of shipping to Necedah National Wildlife Refuge has remained relatively consistent. Focal behavioral observations were collected for 2005 and 2006 with half the colts being raised in 1 facility and half in the other. We have compared the amount of time spent in each type of behavior and have related behavior to subsequent survival and wildness for the 2005 releases.