Study

The seasonal decline in clutch size: an experiment with supplementary food in the kestrel, Falco tinnunculus

  • Published source details Aparicio J.M. (1994) The seasonal decline in clutch size: an experiment with supplementary food in the kestrel, Falco tinnunculus. Oikos, 71, 451-458.

Actions

This study is summarised as evidence for the following.

Action Category

Provide supplementary food for raptors to increase reproductive success

Action Link
Bird Conservation
  1. Provide supplementary food for raptors to increase reproductive success

    A randomised, replicated controlled study of kestrels Falco tinnunculus in Cuenca, central Spain, in 1985-92 (Aparicio 1994) found that food-supplemented breeding pairs laid earlier and had larger clutches than control pairs that had receive no food supplementation, and pairs fed from earlier (28th February, at least 50 days before laying vs. 17th April, 17 days before laying) laid earlier than late-fed pairs (average laying date of 30th April for nine early-fed pairs and May 9th for seven late-fed vs. May 15th for 15 controls; average of 5.1 eggs/clutch for fed pairs vs. 4.3 for controls).  The onset of laying was not affected, but the average laying date was earlier.  Supplementation affected clutch size independently of laying date.  In control pairs, there was a seasonal decline in clutch size, but this decline was not seen with supplemented pairs.

     

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