Study

Supplemental food and laying date in the European starling

  • Published source details Källander H. & Karlsson J. (1993) Supplemental food and laying date in the European starling. The Condor, 95, 1031-1034.

Actions

This study is summarised as evidence for the following.

Action Category

Provide supplementary food for birds or mammals

Action Link
Farmland Conservation

Provide supplementary food for songbirds to increase reproductive success

Action Link
Bird Conservation
  1. Provide supplementary food for birds or mammals

    A replicated and controlled study in grasslands in southern Sweden between 1982 and 1990 (Källander & Karlsson 1993) found that common starling Sturnus vulgaris supplied with supplementary food showed only occasional differences in egg weight, no differences in clutch size or nestling weights and fledging rates were actually lower in fed nests in 1990 (4.3 young/nest for fed nests vs 5.6 for controls). However common starlings supplied with food began laying significantly earlier than controls (first laying date 21st April-5th May for fed nests vs 22nd April-10th May for controls). There were no such differences between nests in the years when supplementary food was not supplied. Supplementary food consisted of approximately 100 g of mealworms placed in small feeders either on the outside or inside of nest boxes, supplied to different colonies in 1982 and 1985 and a subset of nests at a third colony in 1990. Feeding began approximately one month before laying started and stopped once all females began laying. Feeding represented more than the daily energetic needs of a pair of starlings.

     

  2. Provide supplementary food for songbirds to increase reproductive success

    A replicated and controlled study in grasslands in southern Sweden between 1982 and 1990 (Källander & Karlsson 1993) found that common starlings Sturnes vulgaris supplied with supplementary food began laying significantly earlier than controls (first laying date of 21st April-5th May for fed nests vs. 22nd April-10th May). There were no such differences between nests in the years when supplementary food was not supplied. However there were only occasional differences in egg weight, no differences in clutch size or  nestlings weights and fledging rates were actually lower in fed nests in 1990 (4.3 young/nest for fed nests vs. 5.6 for controls). Supplementary food consisted of approximately 100g of mealworms placed in small feeders either on the outside or inside of nest boxes, supplied to different colonies in 1982 and 1985 and a subset of nests at a third colony in 1990. Feeding began approximately one month before laying started and stopped once all females began laying. Feeding represented more than the daily energetic needs of a pair of starlings.

     

Output references
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