Detailed Survey Method

Willow Tit Survey Method


Our survey will focus on surveying approximately 48 tetrads where Willow Tit have been recorded in the past, plus other suitable habitat. Willow Tits are generally associated with wet woodlands or rough unimproved grassland sites bordered by thick, young woody scrub. However, they are not exclusively birds of wet habitats and can be found in drier woodlands and in very wide unmanaged hedgerows. Please note some of the records we have came only with a place name, with no grid reference, in which case the tetrad has been generated as the closest to the named site. For the survey please identify the most suitable habitat within each tetrad, using aerial photographs in advance, or by visual inspection on arrival at the site.


The survey commenced in 2017 but will continue in 2018, so if you are able to help that would be appreciated. The survey period will run from late January/early February to late March. The survey involves two visits to each tetrad, with the repeat visit undertaken at least two weeks after the first if no birds are found.


Surveys need to be undertaken in relatively fine weather; dry days with little wind. In these conditions Willow tits are most likely to hear and respond to the song playback. The time of day surveys are carried out is not important, although mornings are generally best. Willow Tit is a difficult species to differentiate from Marsh Tit, please familiarise yourselves by reading the identification article, listening to the mp3 file provided and watching the BTO video guide. Do not be afraid to say you couldn’t decide, some silent birds will defy even the experts, it is better to be open and give us more accurate information.

The transect

During each survey a transect walk is conducted within areas of suitable habitat in the square. This could be a linear or zig-zag type walk depending on the size and layout of the site and ease of access. The exact route is decided by the surveyor on site to allow sensible routes to be determined and to ensure unsafe or inaccessible areas (such as very wet, swampy woodland) are avoided. Please annotate a map with the route taken to give an idea of coverage. Every 100 metres (approximately 110 big strides, 150 normal strides, but could be 200 strides where the ground is steep or vegetation is hard to walk through) along the transect walk the recording of Willow Tit song is played for two minutes (the same recording is to be used by all surveyors). Surveyors can use an mp3 player with speaker attached or a smart phone.

Willow Tit are territorial throughout the survey period and if present are likely to respond and will often come quite close to the surveyor and call back. Sometimes other species come and investigate, including Marsh Tit, so it will be important to hear the bird call back to confirm which species it is. In the absence of a vocal response please make a note of this on the sheet, provide a description of the bird and indicate how sure you are of the identification.

If Willow Tit do respond to the song playback, stop the tape and record the sighting on the survey form and then continue the transect walk. If there is no response during the two minutes of the playback, a further two minutes should be spent listening for a delayed response from the birds before continuing with the transect walk. Record the number of Willow Tit seen on the form (if more are suspected but cannot be confirmed, put the number confirmed plus – e.g. 2+). If no Willow Tit are seen at the stop put a ‘0’ on the form. Should Willow Tit be seen between stops, use the next available section on the form, but make it clear in the Willow Tit sighting notes that the birds were recorded between playback stops.   Make a note of assumed Marsh Tit sightings in the notes of sighting section.

If you get a faint response from some distance away and need to confirm it is a Willow Tit, feel free to move closer to the bird and play the call again. Note down the grid reference and habitat information from the point where you eventually confirm the Willow Tit but make sure when you begin walking the transect again you ensure you are a good 100 metres from all previous call-back stops.

We encourage you to make up to 10 ‘stops’, on your transect walk if there is sufficient suitable habitat. However many squares will have less habitat to survey and will require fewer stops. If, in conducting your transect, you encounter totally unsuitable habitat (e.g. dense, mature conifer plantation) walk through this and make the next stop the point at which the habitat becomes more promising for Willow Tit.

If Willow Tit are found, no second visit to the square is required, but if you have adequate time we would like you return and repeat the same transect at least two weeks after your first visit in order to try and confirm the abundance of Willow Tit territories. If no Willow Tit are found during the first visit a second visit is definitely required.

Please see the example survey sheet which shows an example recording scenario.

‘Roving records’

Whilst the key aim of this survey is to prove presence or absence of Willow Tit in tetrads where they have been recorded in the past, please do submit Willow Tit sightings collected from elsewhere in Cornwall during the survey period. Please record these on the separate form provided ensuring there is a grid reference, location and date and ideally use the playback method to confirm Willow Tit rather than Marsh Tit.


It is very important that we do not survey on land where we have been unable to agree access permission. CBWPS will try and contact landowners to request access if there is no public access to the site.  If permission is gained the surveyor will need to ring the landowner(s) a few days before their intended survey to check that this suits the landowner. This can be a useful opportunity to find out where it is possible to park and whether there are any livestock/potential hazards in the land to be visited. Where it has not been possible to find landowner details or access has been denied, surveyors can survey from roads and public footpaths but it is important to adhere closely to rights of way and avoid conflict with landowners. Should the surveyor wish to cold-call on possible landowner with suitable habitat on the day, to request additional access permission, feel free to do so unless the landowner has already refused access or been found not to own any of the land in question. A refusal/negative ownership will be noted on the overview map as will farms/properties to which CBWPS has already written but received no response.

Habitat recording (optional)

The survey form includes space for a small amount of habitat recording, which, if you feel able to do this, will help us get an idea of the age and management of the woodland and availability of suitable nest sites (i.e. very soft standing deadwood or dead limbs on live trees). Some habitat variables should be recorded from the song playback stops and others between stops. Ignore habitat that is totally unsuitable for Willow Tit (i.e. managed farmland such as improved/semi-improved grasslands that are clearly grazed and/or cut regularly – bright green, shorter swards with no scrub).

Habitat can be recorded during visit one or two or can be split across the survey visits if you wish.

  • habitat type (whether coniferous, broadleaved woodland etc.)
  • habitat management (often the habitat will be unmanaged but there may be grazing, there may be evidence of past coppice management or clear-felling in plantation woodlands).
  • Density – openness of tree canopy (gives an idea of how mature/established the woodland is)
  • Density – openness of scrub layer (may help to give an indication of whether Willow Tit prefer more open habitat or areas with a well-developed, dense shrub layer).
  • Habitat to record between stops

Numbers of large/mature trees to give an indication of the maturity of the woodland

Amount of dead wood (standing or boughs) to give an indication of with nest site potential

Photographs (optional)

Photographs can be very useful to substantiate your choice of habitat type. If possible, one should be taken of representative section of habitat you survey. At least two images should be taken from a playback stop, one a broad, representative view of the immediate surroundings and one photo, slightly more close-up, showing something of the ground vegetation and structure at ground level. Make sure the photographs can be related to particular stops. There are phone apps that attach grid references to your photos, or you can take a photograph of the relevant ‘stop’ on your survey form.


  • MP3 player with separate speaker or smart phone with separate speaker, integral speaker
  • Compass, or ideally a GPS, or smart phone with GPS app
  • Binoculars
  • Mobile phone, vital if lone working
  • Clipboard, recording sheets and pencils
  • Authorisation/explanatory letter from CBWPS
  • Camera
  • Personal protective clothing
  • Appropriate first aid kit

Key Contacts

Dave Parker (CBWPS)  [email protected] Tel 07932 354711

Claire Mucklow (RSPB)  [email protected]  Tel 07764 230246

Completed forms should be scanned or posted to Dave Parker at 2 Boslevan, Green Lane Marazion TR17 0HQ, with a request for further squares if required, but by 10 April at the latest.