Twite national sample survey in the UK in 1999

Royal Society for the Protection of Birds

Description

This dataset contains results from the first comprehensive survey of breeding twite in the UK. A random subsample of the UK breeding range was surveyed to arrive at a population estimate, and as such the dataset does NOT contain all breeding locations of twite in the UK in 1999. There were an estimated 10 000 pairs of breeding twite in the UK in 1999, with the range lying between 6000 and 15 000 pairs. The majority, 9948 (95% confidence intervals 6293-14 586) pairs, was recorded in Scotland and England. Joint Nature Conservation Committee (JNCC) and English Nature (now Natural England) helped fund this survey as part of the Statutory Conservation Agencies/RSPB Annual Breeding Birds Scheme (SCARABBS). Thanks also to all the staff and volunteers who assisted with data collection.

Geographic Description

UK wide. Surveys were carried out in areas of Scotland and England where the combined range of twite were presented in the 1968-72 and 1988-91 Atlases (Sharrock 1976, Gibbons et al 1993). In Wales and Northern Ireland, the Atlas ranges were small so a complete census of known and suspected breeding sites based on local knowledge was attempted.

Data quality

No known issues. The data has been mapped and thoroughly checked against the published paper before upload to the NBN.

Methods

In Scotland and England, three visits were made to a stratified random sample of 1km squares, walking modified point transects at 200m intervals. Whilst recording was continuous at 100m intervals within suitable breeding habitat, observers made five-minute stops to scan and listen for twite. Habitat cover was recorded to the nearest 10%. Supplementary records were collated from Wales and Northern Ireland. Several methods were used to produce population estimates, with bootstrapped confidence intervals.

Citation

Please acknowledge the Royal Society for the Protection of Birds (RSPB), Joint Nature Conservation Committee (JNCC), English Nature (now Natural England) and SCARABBS (Statutory Conservation Agencies and RSPB Breeding Birds Scheme) in any use of the data.

Rights

CC-BY

Digitised records