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Providing evidence to improve practice

Action: Provide supplementary food to allow the rescue of a second chick Bird Conservation

Key messages

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A small controlled study in Spain found that second chicks from lammergeier Gypaetus barbatus nests survived longer if nests were provided with food, allowing one chick to be rescued.


Supporting evidence from individual studies


A small controlled study in the Spanish Pyrenees in spring 2004-5 and 2008 (Margalida et al. 2009) found that second-hatched lammergeier (bearded vulture) Gypaetus barbatus chicks from two nests provided with supplementary food survived for nine days, as opposed to seven, five and four days for a partially-supplemented nest and two control (unfed) nests, respectively. In a third supplemented nest (in 2008), the second-hatched chick survived for five days and was removed to be hand-reared and incorporated into a captive-breeding programme. Supplementary food consisted of 2-3 kg of dead rabbits within 100 m of the nests every two days from the hatching of the first chick until the death (or removal) of the second chick. The partially-supplemented nest was provided with food on just one day.


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.