Characteristics of avian mortality at a north Florida television tower: A 29-year study

The study of birds killed at the WCTV television tower in north Florida ove r a 29-yr period is one of the longest of its kind. A total of 44,007 indiv iduals in 186 species was collected, and over 94% of the total number of in dividuals were Neotropical migrants with the Red-eyed Vireo (Vireo olivaceo us) the most frequent. Two factors changed during the study period: tower h eight and scavenger control. Analysis of these factors suggest that towers approximately 94 m or lower may not pose as great a threat of avian mortali ty as caused by towers 200 m or greater. Absence of scavenger control corre sponded with a 71% decline in the number of individuals found beneath the t ower. Any study of avian mortality at communication towers must directly ad dress the problem of removal of injured and dead birds by scavengers to mak e an accurate measure of mortality.