Supplementary food has a limited impact on reproductive success in American coots Fulica americana in Manitoba, Canada


This study is summarised as evidence for the following.

Action Category

Provide supplementary food for rails and coots to increase reproductive success

Action Link
Bird Conservation
  1. Provide supplementary food for rails and coots to increase reproductive success

    A randomised, replicated and controlled study in wetlands in Manitoba, Canada, in 1987-9 and 1991 (Arnold 1994), found that American coots Fulica americana laid clutches significantly earlier and had significantly larger clutches when provided with supplementary food (steam-rolled corn and commercial rabbit food), compared with control (unfed) pairs (average of May 5th for first laying date for fed 309 pairs vs. May 7th for 386 unfed pairs). However supplementary food did not affect egg size or laying rate and the authors note that feeding only accounted for 1% and 3% of the variation in laying date and clutch size respectively. No data was presented on the hatching rate or survival of chicks.


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