Crested tit wintering survey in the UK, 1992-1995

Royal Society for the Protection of Birds

Description

These are the data from the first survey conducted on crested tit since 1979/80. The data were collected as part of a wider survey of pinewood birds (Scottish Crossbill and Capercaillie). Surveys were conducted over 3 winters, 92/93, 93/94 and 94/95, by walking transects in areas of suitable habitat (native pine forest and plantation woodland) near and within the known distribution of Crested tits. The results were used to derive a population estimate for Scotland of between 5600 and 7900 birds. This dataset contains the raw data. Details explaining how populations were derived can be found in the published paper (Summer et al 1999). Crested tits showed a clear preference for Scots Pine both within ancient native pinewoods and other woodlands. The results of this survey suggest that Crested Tits will continue to benefit from planting of Scots pines if the woods develop a heather field layer. However, they will not benefit from spruce plantations.

Geographic Description

The breeding range of the Crested tit, Moray Firth area in Scotland.

Data quality

These data have been gathered by trained field-workers and the data are of a high quality. The data have been mapped and checked for sensitivities and typographical/geographical errors.

Methods

The woodlands in the Moray firth area, which encompasses the breeding range of the Crested tit population in Scotland, were stratified according to ancient native pinewoods and other woodlands, which were primarily conifer plantations. Forty transects within ancient native pine woodlands were selected systematically and 81 transects were selected in other woodlands using random six figure grid refs which fell within this range.<br />

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The transects were all 2KM long and in a triangular formation, they were drawn such that the gird reference fell half way along the primary side of the transect triangle. <br />

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Once a bird or group of birds was found, 3 measurements were taken; the angle between the bird/group and the transect line, the distance from the observer to the group and the number of birds in the group. Birds were most likely to be detected by calls so there was no difference in detection between birds on the far or near edge of the group. Estimates of the bird density were then calculated using the DISTANCE programme. This dataset contains the raw sightings. Further details of how populations were derived are explained further in Summer et al (1999).

Citation

Data reproduced with the permission of RSPB

Rights

CC-BY

Digitised records