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Providing evidence to improve practice

Action: Mark eggs to reduce their appeal to egg collectors Bird Conservation

Key messages

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A single before-and-after study found that marking eggs greatly increased the number of chicks fledging from six raptor nests in Australia in 1979 and 1980.


Supporting evidence from individual studies


A small before-and-after study in the Flinders Ranges, South Australia (Olsen et al. 1982), found that twice as many young fledged from five peregrine falcon Falco peregrinus nests (12 young fledged from 16 eggs) and one wedge-tailed eagle Aquila audax nest (one chick from two eggs) in 1980, when eggs were marked with a single line drawn in black, waterproof ink, as in 1979, when no eggs were marked (6/15 and 0/2 fledged respectively).


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.