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Individual study: Supplementary feeding shortens incubation time and increases hatching success for blue tits

Published source details

Nilsson J. & Smith H.G. (1988) Incubation feeding as a male tactic for early hatching. Animal Behaviour, 36, 641-647


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

Provide supplementary food for songbirds to increase reproductive success Bird Conservation

A replicated, paired site study in 1984-1985 in 17 experimental and 17 control pairs of blue tit Parus caeruleus nests in Lund, Sweden (Nilsson & Smith 1988), found that blue tit pairs that were artificially provisioned with food exhibited significantly greater reproductive success. Supplementary feeding significantly shortened the length of the incubation period. The probability that an egg would hatch was higher in provisioned nests than in control nests (98 and 90% of 198 and 199 eggs respectively). However, nestling survival up to 13 days did not differ between the pairs. Each pair was selected so that the last egg in both clutches was laid on the same date and the pairs nested in similar habitats. Four days after the last egg was laid, a container with 7 g of mealworms was placed into the experimental nest, while an empty container was placed into the control nest. Age and wing length did not differ between dyad pairs.