Habitat and topographical correlates of breeding site desertion by Ring Ouzels in the Moorfoot Hills, south-east Scotland (unpublished)
Using a Landsat 7 satellite image and a supervised classification method, a habitat map for the Moorfoot Hills was produced. This map was very accurate in predicting Bracken and grass habitats, and reasonably accurate for Heather and Heather-mosaic habitats. Ring Ouzel breeding site occupancy was determined during the periods 1952-1985 and 1998-2000, and sites were classed as either occupied or deserted during the latter period. Breeding sites were more likely to still be occupied during 1998-2000 if they were at higher altitudes and had more Heather cover within radii of both 200m and 450m. In addition, continued occupancy during 1998-2000 was more likely if there were either few or many habitat patches, and less forestry within a 450m radius. Using only topographic variables, potential breeding sites were predicted and the habitat surrounding them was compared to actual breeding sites. Actual breeding sites were more likely to have at least one pixel of Heather or grass-Heather mosaic within 100m than potential breeding sites. After accounting for this difference, there were no habitat differences between actual and potential breeding sites within radii of 200m or 450m. These results suggest that those breeding sites at higher altitudes and with a higher Heather or Heather-mosaic cover within 450m were less likely to have been deserted.
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