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Individual study: Cross-fostering reduces pairing success in great tits Parus major but not in blue tits P. caeruleus or pied flycatchers Ficedula hypoleuca in woodlands in southern Norway

Published source details

Slagsvold T., Hansen B.T., Johannessen L.E. & Lifield J.T. (0) Mate choice and imprinting in birds studied by cross-fostering in the wild. Proceedings of the Royal Society of London. Series B: Biological Sciences, 269, 1449-1455.


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Foster eggs or chicks of songbirds with wild non-conspecifics (cross-fostering) Bird Conservation

A replicated and controlled study in woodlands in southern Norway in 1998-2000 (Slagsvold et al. 2002) found that cross-fostering did not affect the recruitment of great tits Parus major (12% of birds raised by blue tits P. caeruleus observed the following year, n = 155 chicks vs. 13% of control birds, n = 196) or pied flycatchers Ficedula hypoleuca (4% recruitment for birds raised by great or blue tits, n = 573 vs. 6% for control birds, n = 935). However, blue tits raised by coal tits P. ater had higher recruitment than controls, or those raised by great tits (18% recruitment for birds raised by coal tits, n = 38 chicks vs. 10% for birds raised by great tits, n = 242 and 7% for control birds, n = 175). Cross-fostering reduced pairing success in great tits (27% pairing success for cross-fostered chicks, n = 11 vs. 95% for controls, n = 20) but not in blue tits (100% pairing success for both cross-fostered and control chicks, n = 17 and 11 respectively) or flycatchers (95% pairing success for cross-fostered chicks, n = 19 vs. 95% for controls, n = 39). All fostering occurred during incubation, with eggs moved between nests before they hatched.