ORGANOCHLORINE RESIDUES IN NESTING KILLDEER, CHARADRIUS-VOCIFERUS, AND THEIR EGGS IN NORTH-DAKOTA

Detectable concentrations of DDE were found in 88% of a nesting Killde er sample (n = 72) collected in northwestern North Dakota. The geometr ic mean DDE concentration for all the Killdeers was 0.17 ppm with a ra nge from 0.02 to 3.49 ppm. Body burden of DDE in males was significant ly higher than that of the females. Adults had significantly higher re sidues than juveniles that had not yet migrated to wintering areas. DD E was found in 100% of the eggs collected (n = 12) but was not correla ted with eggshell thickness.