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Providing evidence to improve practice

Individual study: Supplementary feeding reduces provisioning female mass loss but does not increase nestling mass in artificially enlarged great tit Parus major broods in woodland and parkland in Scotland

Published source details

Johnston R.D. (1993) The effect of direct supplementary feeding of nestlings on weight loss in female Great Tits Parus major. Ibis, 135, 311-314


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 adult survival Bird Conservation

A randomised, replicated and controlled paired study in parkland and mixed woodland in southern Scotland in spring and summer 1990 (Johnston 1993) found that great tit Parus major females with artificially enlarged broods lost significantly less weight whilst provisioning young when nestlings were provided with supplementary food, compared to females with control (enlarged but not fed) broods (average of 2.2 g lost between day ten of incubation and day 13 of provisioning for experimental females, n = 8 vs. 2.9 g for control females, n = 7). There were no data on survival of adults. Broods were enlarged by the addition of three nestlings (added after hatching). Supplementary food consisted of an average of 2.2 g of minced meat and nutritional supplements fed twice daily to half the experimental brood on days six through 12 after hatching. This represents most of a nestling’s daily energetic requirements. This study also investigated the impact on the nestling growth, discussed in ‘Provide supplementary food to increase reproductive success’.

 

Provide supplementary food for songbirds to increase reproductive success Bird Conservation

A small randomised and controlled paired study in parkland and mixed woodland in southern Scotland in spring and summer 1990 (Johnston 1993) found that great tit Parus major nestlings in eight artificially enlarged broods were no larger at 15 days old when provided with supplementary food, compared to nestlings from seven control (enlarged but not fed) broods. Broods were enlarged by the addition of three nestlings (added after hatching). Supplementary food consisted of an average of 2.2 g of minced meat and nutritional supplements fed twice daily to half the experimental brood on days six through 12 after hatching. This represents most of a nestling’s daily energetic requirements. This study also investigated the impact on the condition of provisioning females, discussed in ‘Provide supplementary food to increase adult survival’.