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Providing evidence to improve practice

Action: Foster eggs or chicks of cranes with wild conspecifics Bird Conservation

Key messages

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A small study in Canada found high rates of fledging for whooping crane Grus americana eggs fostered to first time breeders (which normally have very low fertility).


Supporting evidence from individual studies


A small study between 1986 and 1991 (Kuyt 1996) found that at least three ‘novice’ breeding pairs of whooping cranes Grus americana in a population in Northwest Territories and Alberta, Canada, successfully raised chicks when their own eggs were substituted for other eggs which were definitely fertile. Novice pairs normally have lower reproductive success than more experienced pairs. At least one pair with low breeding success was also provided with a fertile egg several days from hatching and successfully raised the chick. This study is also discussed in ‘Use captive breeding to increase or maintain populations’, ‘Release captive-bred individuals’ and ‘Foster eggs or chicks with wild non-conspecifics (cross-fostering)’.


Referenced papers

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2019) Bird Conservation. Pages 141-290 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.