ELF Communications System Ecological Monitoring Program: Bird Species and Communities: Annual Report 1993

Abstract

This investigation was designed to detect effects of electromagnetic (EM) fields produced by extremely low frequency (ELF) antenna systems on bird species breeding in or migrating through Wisconsin and Michigan. Specifically, we seek to determine if bird species richness and abundance differ between areas that are close to the antenna and those that are far enough away to be unaffected by the antenna. We are pursuing this question at both the community and species level. Characteristics examined include total species richness and abundance, abundances of common bird species, and abundances of birds within selected guilds. Our monitoring program has included bird censuses in both states over a five month period from May to September, from 1986 onwards. Additional data were collected in August-September 1984 and in June 1985, in both states. Bird censuses were terminated in Wisconsin after 1989 but are continuing in Michigan. No consistent patterns are evident to demonstrate that changes in bird abundance differ between treatment relative to control segments in Michigan after the antenna became operational. No significant interactions found at the community or species level are always repeated in subsequent seasons. In addition, interactions in guild or individual species abundance patterns that exist between treatment and control areas in any season are not repeated in subsequent seasons. Number of significant interactions found at many levels of the analyses were not greater than the number expected by chance alone and are unlikely attributable to electromagnetic fields.