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York Bight apex fish and shellfish are more likely caused by sources 

 other than sewage sludge. 



2.3 ALGAL SLOOMS 



Rapid algal population increases (blooms) have been observed on a number 

 of occasions in the Mew York Bight (Section 11.2). Such blooms can 

 lead to fish kills caused by natural toxins produced by the algae, or by 

 the depletion of oxygen due to algal decomposition. Such blooms occur 

 naturally in many parts of the world ocean, and since historical records 

 indicate that blooms may have occurred often in the past in the New York 

 Bight, those blooms now observed might also be of natural origin (Section 

 11.2). In some instances, algal blooms are caused by over-fertilization 

 of aquatic ecosystems with nutrients, such as phosphorus and nitrogen, in 

 a process called eutrophication. There is evidence that portions of the 

 New York Bight might be seasonally eutrophic. However, the predominant 

 sources of nitrogen, the probable causative agent, are the inputs of 

 estuarine waters, coastal wastewater discharges, and land runoff into 

 the New York Bight apex (Sections 6.3 and 11.4). Sewage sludge comprises 

 only a minor fraction (approximately 6 percent) of the total nitrogen 

 load to the New York Bight apex and therefore is not a causative agent 

 in the initiation of nuisance algal blooms (Section 11.4). 



2.4 FISH KILLS 



The occasional "fish kills" that have occurred in the New York Bight are 

 generally caused by oxygen depleted bottom waters which can form during 

 stratified summer conditions. In general, few finfish are killed by 

 oxygen depleted bottom waters since they are generally able to actively 

 avoid the oxygen depleted water. However, shellfish, which are typically 

 immobile can be killed in large numbers if anoxic conditions persist. 

 The most significant recent fish kill took place in 1976 and has been 

 referred to as the "1976 anoxia event." 



Extensive Federal, state, and academic studies of the 1976 anoxia event 

 have led to the conclusion that the event was the result of several 

 anomalous natural conditions and that sewage sludge dumping in the New 

 York Bight was not a causative factor (Section 11.5). Recent research 

 strongly supports the conclusion reached by the 1978 FEIS that meteor- 

 ological conditions of the previous winter and spring, tide and v^ind 

 driven circulation patterns in the Bight, the formation of an unusually 

 stable thermocline, and the existence of an unusually extensive and 

 persistent algal bloom led to the 1976 anoxia event and its accompanying 

 shellfish kill (Section 11.5). The literature also establishes that 

 anoxic conditions occur naturally in coastal water bodies throughout the 

 world, and that the New York Bight has historically experienced repeated, 

 although less severe, anoxic episodes (Section 11.2). 



2.5 FISH AND SHELLFISH DISEASES (INCLUDING FIN ROT) 



Surveys conducted in and around the New York Bight have reported inci- 

 dences of fish disease conditions including black gill, shell erosion, 

 finrot, ulceration, lymphocystis, tumors, skeletal anomalies, parasitic 

 infestation, and larval mutagenesis. Some of these diseases may be 



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