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F.J. Ligas

Publications and source records attributed to F.J. Ligas.

2 recordsLinked to original sources

Residues of organochlorine pesticides, polychlorinated biphenyls, and mercury in bald eagle eggs and changes in shell thickness--1969 and 1970

Twenty-three bald eagle eggs collected in Alaska, Maine, Michigan, Minnesota, and Florida during 1969 and 1970 were analyzed for organochlorine pesticides, polychlorinated biphenyls, and mercury. All eggs contained residues of DDE, dieldrin, PCB's, and mercury. Average residue concentrations were lowest in eggs from Alaska. Significant eggshell thinning has occurred among eggs from most major areas sampled. Some eggs contained DDE residues of the same magnitude as those that produced shell thinning in experimental species. High dieldrin residues in some eggs could be having an adverse effect on reproductive success.

Pesticides Monitoring Journal

Organochlorine and heavy metal residues in bald eagle eggs

Bald eagle eggs collected in 1968 from nests in Wisconsin, Maine, and Florida all contained residues of DDE, DDD, dieldrin, heptachlor epoxide, and polychlorinated biphenyls. Many also contained traces of DDT. Eggs from five nonproductive nests sampled in Maine contained much higher residues than did eggs collected from either productive or nonproductive nests in Wisconsin and Florida.

Pesticides Monitoring Journal