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for the decline is unclear. Chromosomal aberrations and 

 elevated mortalities have been found in the eggs and larvae 

 of Atlantic mackerel ( Scomber scombrus ) taken from the New 

 York Bight Apex. Among early embryo stages, for example, 

 samples with the lowest mortalities were those most distant 

 from the shoreline or from major dumping sites. 



As was suggested earlier, toxicant effects such as fish 

 diseases, skeletal anomalies and developmental failures 

 reflect the total contamination of the Bight, rather than the 

 result of sewage sludge Q'sposal alone. Sewage sludge disposal 

 is likely to contribute to tnese problems, but is not the 

 sole or major cause at present. 



Waters flowing from the Hudson-Raritan Estuary and smaller 

 local estuaries sometimes support extremely high levels of 

 primary production and standing stocks of chlorophyll. Of 

 particular concern is biological oxygen demand (BOD) in botton 

 waters of the Apex resulting from this productivity versus 

 BOD associated with ocean dumping and particulate matter washed 

 out of the Estuary. Recent analyses clarify the relationships 

 among these sources. 



Prior to the onset of stratification in May, most of the 

 primary production that occurs in the plume of the Hudson- 

 Raritan Estuary is exported from the Apex across the continental 

 shelf. Production during this period is not a source of oxygen 



