11-101 



1975) , population simulation models were constructed for population 

 dynamics of winter flounder and menhaden subject to plant-induced 

 mortalities. We did not construct similar models because we felt 

 that to make the following assumptions was inadequate and inappropri- 

 ate in the case of New Haven Harbor: 



1) The area modeled represents a discrete population, sub- 

 ject to limited immigration or emigration of any life- 

 history stages; 



2) The base population of adults and potential recruits may 

 be adequately estimated by either: 



a) use of published density estimates for other areas; 



b) application of trawl data to arbitrarily defined 

 areas without verification that stations trawled are 

 representative of the areas defined; 



c) limited, size-selective mark and recapture studies. 



3) Natural and fishing mortality rates may be chosen from 

 published estimates from locales outside the study area. 



We believe that there is no discrete (distinguishable as 

 separate from Long Island Sound populations) resident population of 

 finfish in New Haven Harbor. For most species, the harbor is apparently 

 an "importer" of finfish eggs, larvae, and possibly juveniles, and an 

 "exporter" of juvenile, pre-adult or adult fish. The importance of the 

 harbor lies not in its instantaneous population but in its use as a 

 nursery. In such a case, to describe a discrete, steady-state popula- 

 tion structure by a mathematical model would be indefensible. 



Because of the high short-term spatial and temporal vari- 

 ability in density and distribution of many finfish species, we would be 

 hesitant to rely on population estimates generated by use of trawl catch. 



