Action Synopsis: Bird Conservation About Actions

Foster eggs or chicks of vultures with wild conspecifics

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

Two small studies, one a New World vulture and one of an Old World species found that single chicks were successfully adopted by foster conspecifics, although in one case this led to the death of one of the foster parents’ chicks.


About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A small study on a farm in North Carolina, USA, in June 1975 (Stewart 1983) found that transferring a 35-40 day-old (American) black vulture Coragyps atratus chick from a nest that was about to be destroyed to a nest containing two 30-35 day-old chicks led to the successful rearing of the fostered chick. However, the smaller of the two chicks originally in the nest was neglected by its parents and died soon after the foster chick was introduced. No data on the fledging success or subsequent survival of the surviving chicks is provided.

    Study and other actions tested
  2. A small study on Sicily, Italy (Di Vittorio et al. 2006), found that a captive-bred Egyptian vulture Neophron percopterus chick fostered into a wild nest in July 2003 was accepted by the foster parents and their two chicks and fledged successfully when approximately 90 days old. The chick was placed in the nest when 60 days old and competed successfully for food. The parents were supplied with supplementary food to ensure that the burden of feeding three chicks was not excessive (vultures tend to raise one or two chicks).

    Study and other actions tested
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. (2020) Bird Conservation. Pages 137-281 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.


Where has this evidence come from?

List of journals searched by synopsis

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Bird Conservation

This Action forms part of the Action Synopsis:

Bird Conservation
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What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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