BTO Winter Thrushes Survey

Mistle Thrush by Tommy Holden

Mistle Thrush on rowan. Photograph by Tommy Holden.

View summary data for survey squares

An introduction to the Winter Thrushes Survey

The online survey is now active. Select to register or login to the survey application from the buttons to the left. The dates for the 'core square' survey are 27 December to 10 January.

The UK countryside supports large numbers of several thrush species through the winter. The Winter Thrushes Survey aims to find out more about their numbers and distribution, and the resources that they need to survive to spring and the next breeding season.

Are we good hosts to these birds? What are the key resources that they need? Over the two winters 2012/13 and 2013/14, the Winter Thrushes Survey will be collecting data to help answer such questions quantitatively for the first time.

What we know already

We already know a great deal about these birds throughout the UK - for example:

  • from Garden BirdWatch and the Garden Bird Feeding Survey, we can see when and where birds are coming into gardens and feeding on artificial foods, and the history of this behaviour since the 1970s
  • from Atlas 2007–11 and the Winter Atlas of 1981/82 to 1983/84, we know their cumulative winter distributions across two periods of years and how variable distributions can be at 10-km scale from winter to winter
  • from BirdTrack we can see the arrival and departure patterns for the more migratory species
  • from the monitoring surveys reported in BirdTrends we know population and demographic trends of the four thrush species that commonly breed  

Gaps in our knowledge

There are several important gaps that the Winter Thrushes Survey can address:

  • How does thrushes' use of habitats (including gardens) vary, by species, geographically and through the winter?
  • How do feeding behaviours vary, again by species, geographically and through the winter?
  • What is the relative importance overall of key habitats such as farmland, gardens and orchards and of the various feeding resources?
  • In what ways do thrush numbers, distribution and feeding behaviour differ between successive winters?

The more information we can gather on these topics, the better we will be able to promote the conservation of these birds.

Survey methods

Read a summary of the survey methods, or download full survey instructions (PDF).

Observers are invited to set up routes, based loosely on 1-km squares, for repeated winter walks. Locations of all thrushes observed, with their habitat and activity are to be plotted online onto a map of the survey route. Walks can be made at any time from mid September to mid April.

A randomly selected set of squares has been set up for synchronised coverage in midwinter. This element of the survey is organised through the BTO's Regional Network.  If you would like to be involved in this part of the survey, please contact your Regional Rep to offer your help.

This is an online-only survey operating through the BTO website. Data may also be submitted on paper for input by survey organisers.