Black crowned night herons as indicators of estuarine health

The results of the organochlorine scan are shown in table 1. Eggs from the Newark Bay colony had significantly higher levels of p, p' - DDD, heptachlor epoxide, oxychlordane, and trans-nonachlor than eggs from the Cape Cod colony. PCB's, trans-nonachlor, oxychlordane, heptachlor epoxide, DDE and DDD were detected in every egg from both colonies. Dieldrin and b - BHC were detected in at least 50% of the eggs from both colonies.