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During nest monitoring in 1990, addled piping plover Charadrius melodus eggs were collected by staff of the New Jersey Department of Environmental Protections Nongame and Endangered Species Program after it was apparent that they were not going to hatch i.e., abandoned eggs, eggs still in nests well beyond the normal incubation period, etc.. Following the nesting season, all eggs were released to the U.S. Fish and Wildlife Service in order to document organochlorine and heavy metal burdens in piping plover eggs and assess the implications of these residues for plover reproductive health. Addled piping plover eggs collected from coastal New Jersey have low level organochlorine contamination; although p,pDDE, polychlorinated biphenyls PCBs, and chlordane metabolites were detected in all samples, the levels do not appear to threaten reproduction. The median concentration of p,pDDE was 0.66 ppm wet weight with a range of 0.20 to 1.1 ppm. Total PCBs ranged from 3.3 to 6.9 ppm wet weight with a median concentration of 3.8 ppm. Total chlordane metabolites sum of heptachlor epoxide, oxychlordane, transnonachlor, and cisnonachlor residues ranged from 0.08 to 0.33 ppm wet weight with a median of 0.18 ppm. Transnonachlor accounted for the largest proportion of total chlordane concentrations followed by oxychlordane, and heptachlor epoxide; cisnonachlor was never a major contributor to total chlordane loading. Other organochlorines in the scan aBHC, bBHC, rBHC, dBHC, rchlordane, achlordane, endrin, mirex, o,pDDE, o,pDDD, o,pDDT, p,pDDD, and p,pDDT were not present above a 0.01 ppm method detection limit; toxaphene was also below detection 0.05 ppm in all samples. Mercury concentrations ranged from 0.299 to 3.63 ppm dry weight with a median concentration of 0.512 ppm. Corrected for percent moisture, mercury concentrations in New Jersey piping plover eggs ranged from 0.077 to 1.07 ppm with a median concentration of 0.164 ppm wet weight. Most of the published literature on piping plovers attributes the initial cause of their demise to habitat loss and hunting, and the continuing limitation of their recovery to habitat loss from coastal development and disturbances such as pedestrian and vehicular traffic, and predation. With the exception of the mercury load in the eggs from Brick Township 1.07 ppm wet weight, the residues detected in this study appear below those thought causative of avian reproductive anomalies. Because the data indicate the possibility of greater contaminant burdens in eggs of piping plovers from breeding areas north of those in this study, additional analyses of addled plover eggs may be warranted. These analyses should focus on mercury and, potentially, isomer specific PCBs; there should also be an effort to include nest locations from north New Jersey e.g., Sandy Hook and southern New York southern shore of Long Island in order to assess the significance of the spatial trend in contaminant concentrations apparent from this study. Any decision to perform additional analyses should consider the overwhelming evidence that habitat loss and disturbance appear to be the primary limiting factors in plover recovery.