Individual study: Supplementary feeding has variable impacts on nutritional status in forest birds in Ohio, USA
Doherty P.F. & Grubb T.C. (2003) Relationship of nutritional condition of permanent-resident woodland birds with woodlot area, supplemental food, and snow cover. The Auk, 120, 331-336
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 woodpeckers to increase adult survival
Another analysis (Doherty & Grubb 2003) of the same data as Doherty & Grubb 2002 found that downy woodpeckers Picoides pubescens did not have higher nutritional statuses (judged by the size of feather growth bars) than woodpeckers in unfed control woodlots. The impact on three songbird species is discussed in ‘Provide supplementary food to increase adult survival – Songbirds’.