North American Crane Working Group


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Ellis, David H. and Gee, George F. Whooping crane egg management: options and consequences. 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. 17-23.


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


Eggs to build captive whooping crane (Grus americana) flocks and most eggs for reintroduction experiments have come from second viable eggs in 2-egg clutches in Canada. Four years ago, egg removal ceased. Based on reproductive rates for years when second eggs were removed and for years when eggs were not removed, we project numbers of young fledging in the wild and in captivity for the 2 most likely egg-management strategies. From existing data sets, we find that reproductive performance was, on average, better during the era of routine removal of the second viable eggs than when no manipulation occurred. Further, the munber of young produced in captivity from the removed eggs, on average, resulted in a doubling of the number of young birds (wild and captive) alive each autumn.