Study

Effect of experimentally altered food abundance on fat reserves of wintering birds

  • Published source details Rogers C.M. & Heath-Coss R. (2003) Effect of experimentally altered food abundance on fat reserves of wintering birds. Journal of Animal Ecology, 5, 822-830.

Actions

This study is summarised as evidence for the following.

Action Category

Can supplementary feeding increase predation or parasitism?

Action Link
Bird Conservation

Provide supplementary food for songbirds to increase adult survival

Action Link
Bird Conservation
  1. Can supplementary feeding increase predation or parasitism?

    A replicated, controlled study at two pairs of mixed habitat sites in Kansas, USA, in the winters 2000-1 and 2001-2 (Rogers & Heath-Coss 2003) found that predation rates on seven species of songbird by Cooper’s hawk Accipiter cooperi and sharp-shinned hawk A. striatus were no higher in an area supplied with supplementary food, compared with control (unfed) sites (two attacks in fed sites vs. no attacks in control sites). Supplementary feeding ran from early December until early March and consisted of four sunflower seed feeders and a 6 x 3 m area beneath them sprinkled with mixed seed. The species studied were dark-eyed junco Junco hyemalis, Harris’s sparrow Zonotrichia querula, song sparrow Melospiza melodia, American tree sparrow Spizella arborea, northern cardinal Cardinalis cardinalis, black-capped chickadee Parus atricapillus (also known as Poecile atricapillus) and tufted titmouse Parus bicolor. The effects of feeding on songbird body condition are discussed in ‘Provide supplementary food to increase adult survival’.

     

  2. Provide supplementary food for songbirds to increase adult survival

    A replicated, controlled study at two pairs of mixed habitat sites in Kansas, USA, in the winters 2000-1 and 2001-2 (Rogers & Heath-Cross 2003) found that seven songbird species had higher levels of visible subcutaneous fat in areas supplied with supplementary food, compared with those in control (unfed) areas. Most differences were significant in both years and both pairs of sites, but differences were always small. Body mass relative to size showed a similar trend, but the differences were not significant. Supplementary feeding ran from early December until early March and consisted of four sunflower seed feeders and a 6 x 3 m area beneath them sprinkled with mixed seed. The species studied were dark-eyed junco Junco hyemalis, Harris’s sparrow Zonotrichia querula, song sparrow Melospiza melodia, American tree sparrow Spizella arborea, northern cardinal Cardinalis cardinalis, black-capped chickadee Parus atricapillus (also known as Poecile atricapillus) and tufted titmouse Parus bicolor. The effects of feeding on predation rates are discussed in ‘Can supplementary feeding increase predation or parasitism?’.

     

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 18

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust