North American Crane Working Group


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Bergeson, Douglas G., Johns, Brian W., and Holroyd, Geoffrey L. Mortality of whooping crane colts in Wood Buffalo National Park, Canada, 1997-99. In: Ellis, David H., ed., Proceedings of the Eighth North American Crane Workshop, 11–14 January 2000, Albuquerque, New Mexico (Seattle, Wash: North American Crane Working Group, 2001), pp. 6-10.


Reproduced by permission of the North American Crane Working Group (NACWG).


Twenty-two whooping crane (Grus americana) pairs with 2 young were monitored in Wood Buffalo National Park (WBNP) over 3 years to determine causes of colt mortality. The family groups were monitored from the ground, air, and with the aid ofradioteiemetry. We attached transmitters to 18 colts: 5 (28%) fledged, 5 (28%) succumbed to cumulative effects (head trauma, stress, exposure and/or infection), 4 (22%) were lost to unknown causes (3 of these went missing after they had lost their transmitters), 2 (11%) were taken by foxes (Vulpes vulpes), 1 (5.5%) was lost to raven (Corvus corax) predation, and 1 (5.5%) died of pneumonia. Of the 22 pairs we monitored, 16 young fledged. Of these, 2 (13%) were the younger sibling.