Blake, John G.Niemi, Gerald JHanowski, JoAnn MCollins, Patrick T2015-02-262017-04-142015-02-262017-04-141991https://hdl.handle.net/11299/187208ANNUAL REPORT: 1991; SUBCONTRACT NUMBER: EO6549-84-011This investigation was designed to isolate 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, 1986-1991. 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 have yet emerged to demonstrate that birds are more or less abundant on treatment relative to control segments in either state after effects of habitat are accounted for. Further, few significant differences have been found at the community or species level; differences in one season or year are not always repeated in subsequent years or seasons. Most differences that exist between treatment and control transects can be attributed to habitat differences or chance rather than to electromagnetic field differences.enELF communications systemExtremely low frequency antenna systemsBird speciesWisconsinMichiganNatural Resources Research InstituteUniversity of Minnesota DuluthTechnical Report