Action Synopsis: Bird Conservation About Actions

Provide supplementary food for gamebirds to increase reproductive success

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

Key messages

A controlled study in Tibet found that Tibetan eared pheasants Crossoptilon harmani that were fed supplementary food laid significantly larger eggs and clutches than control birds. Nesting success and laying dates were not affected.


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 controlled trial at two scrubland sites near Lhasa, Tibet, during 1996 and 1999-2001 (Lu & Zheng 2003) found that Tibetan eared pheasants Crossoptilon harmani that were fed supplementary food (mainly highland barley provided by Buddhist nuns every day throughout the year) laid significantly larger eggs and had significantly larger clutches than control (unfed) birds, although the differences were small (average of 55 g/egg for 55 eggs from fed birds vs. 53 g/egg for 32 controls; average of 7.7 eggs/clutch for 23 fed birds vs. 7.0 eggs/clutch for 28 controls). Fed birds did not have higher nesting success or lay earlier than controls (fed birds: 96% of 144 eggs fertilised, 94% of these hatched, average first laying date of 6th May for 27 clutches; control birds: 98% of 124 eggs fertilised, 97% of these hatched, average first laying date of 8th March for 35 clutches). No data is provided on fledging success or survival of 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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