11-96 



New Haven Harbor is affected by menhaden feeding; they travel in dense 

 schools filtering phytoplankton and zooplankton from the water, their 

 large numbers often altering water quality (reducing dissolved oxygen, 

 increasing ammonia concentrations) by their physiological processes. 

 Abundance of adult bluefish in the harbor may be directly related to the 

 abundance of this prey species. Harbor water quality is sufficiently 

 poor to cause or enhance mass mortalities of menhaden, which may be due 

 to excessive temperature or industrial pollutants and/or low dissolved 

 oxygen concentrations. These adverse conditions increase predation 

 success by the bluefish and impingement by New Haven Harbor Station. As 

 with Atlantic herring. New Haven Harbor is important only to a small 

 fraction of the Long Island Sound contingent of this widespread and 

 abundant species. 



A tewife 



A relatively small niimber of alewives probably ascend the 

 tributary streams of New Haven Harbor to spawn in the spring. The abun- 

 dance of this species is so low as to preclude substantial trophic 

 importance. Alewives utilize New Haven Harbor as a zone of passage to 

 their spawning groiinds. In comparison with the rest of Long Island 

 Sound, New Haven tributaries are of no quantitative significance in 

 alewife reproduction. 



Bluebaok Herring 



Bluebacks, like alewives, may breed in New Haven tributaries, 

 but do not do so in important quantities. Also, like alewives, they are 

 not significant in food webs because of their relative scarcity. 



