10 



Nodal analysis, for both constancy and fidelity, was applied to 



interface the results of the two classifications. Following the 



convention presented in Boesch (1977), a constancy index was calculated 



as C . . = a . ./(n.n .). where a., is the number of occurrences of 

 ^J id *- 3 W 



Species-Group i in Site-Group J and n. and n. are the numbers of 



entities in each group considered. The fidelity index was calculated as 



F..= (a.. .n.)/(n. . a..), the symbols having the same meaning as 

 ^J 1*3 3 3 3 3 t>3 



above. Fidelity values less than 1 suggest a negative relationship and 

 values of over 1 a positive relationship between a species-group and a 

 site-group. 



RESULTS AND DISCUSSION 



Depth, Temperature and Salinity 



The depths of the 56 stations sampled range from 7 to 140 feet, 

 i.e. 2-43 m (Table 1). All stations exceeding 70 feet in depth are 

 offshore of the outer islands and most inner Bay stations are in the 

 25-50 foot depth range (Fig. 5). Depths are measured by fathometer and 

 are not corrected for tidal stage. 



Bottom water temperatures in April range from 2.9 to 6.3 C with 

 most stations being between 3.0 and 5.0 C. Statistical analysis of 

 water temperature and depth indicates that vernal warming of surface 

 waters is already well progressed by April. This is a very highly 

 significant relationship, p > .9999, with a correlation coefficient of 

 -0.60222. With the exception of two stations, salinity throughout the 

 Bay varied within the narrow range of 30.3 - 32.9 /oo (Table 1). The 

 two stations outside of this range are the relatively shallow stations 

 35 and 41 with salinities of 25.6 and 19.8 /oo, respectively. Heavy 



