Advancement of laying of great tits by the provision of food


This study is summarised as evidence for the following.

Action Category

Provide supplementary food for songbirds to increase reproductive success

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

    A controlled cross-over study in southern Sweden in 1972-3 (Källander 1974) found that great tits Parus major nesting in an 8 ha (1972) or 6 ha (1973) area of oak-hazel woodland supplied with supplementary food began laying eggs significantly earlier than great tits in an adjacent 16 ha or 18 ha control (unfed) area. The difference was significant irrespective of whether all females, one year-old females or older females were examined (average laying date of 1st-5th May for 44 nests in fed areas vs. 6th-11th May for 75 control pairs). Supplementary food consisted of 32 or 33 trays positioned throughout the wood and provided daily with 20-35 g of mealworms from 11th-27th April 1972 and between 10th April and 14th May 1973. On average there were 2 trays/territory in 1972 and 1.5 trays/territory in 1973. The authors note that other species including wood nuthatches Sitta europea and chaffinches Fringilla coelebs also took food from the trays.


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 21

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 ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust