Information collected during this single inspection was used to build a logistic model which allowed the correct classification of most of the dangerous pylons missed in the first inspection. A single under-line inspection identified 78% of the pylons causing bird casualties in the area, which were responsible for 91% of the deaths. Modelling the presence of carcasses under the pylons was used to identify the pylons which concentrate casualties, so that a 'preferred pylon' approach could be used to allocate mitigation resources. Most mortality (97%) could be eliminated if all technically dangerous pylons were modified, but these would entail 67% of the pylons in the study area. Univariate analysis revealed that the technical design of the pylons was very important in determining the potential danger of electrocution (metal crossbows were found to be the most dangerous design, followed by earthed flat pylons and vaults). Casualties occurred in a fairly contagious pattern, since 50% of deaths took place on only 2% of the visited pylons, and 50% of the killing pylons accumulated 80% of the victims. The number of electrocution victims per killing pylon ranged from 1 to 12.
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