(b) Faunal Similarity . A number of coefficients for measuring 

 faunal similarities are available CSanders, 1960; Horn, 1966; Whittaker, 

 1967; Lie and Kelly, 1970; Bray and Curtis, 1975; Grassle and Smith, 

 1976). However, most of the available coefficients consider only the 

 number and rank of common species and not the distribution of individuals. 

 The Morisita's index (Morisita, 1959), which takes into consideration 

 both the number of species in common and the number of individuals shared, 

 is utilized in this study. Many authors in the past have used this index 

 with a greater degree of success than other overlap coefficients (Ono, 

 1961; Barnard, 1970; Mauchline, 1972; Bloom et al . , 1972; Gage and 

 Geekie, 1973; Menzies, 1973; Paul, 1973; Farrell, 1974; Marum, 1974; Gage, 

 1975; Mahade/an, 1979). The computational formula for the Morisita's 

 index is 



CA = 2 Z^ . ^ n.. n,./ (A +A ) N N 

 1-1 11 2i 12 12 



where 



A =S^ . , ^i (^i-1) 

 1 1=1 



■\ - y^ nw. (n„ .-1) 



and ^2 ^ i=l ^1 ^1 



Nj (Nj -1) 

 n.. (n^.-i: 

 N, (N, -1) 



where N^ and N2 are the total number of individuals in sample one and two, 

 respectively, nj ^ and n2i are the number of individuals in the ith species 

 of sample one and two, respectively. The value of CA is about one when the 

 two samples are identical and zero when no common species are present. 

 The index is relatively free from sample size effects. 



Faunal similarity comparisons were conducted between Saloman's (1976) 

 collections and this study's collections. Each station was considered as 

 a composite over nine transects. 



Ill . RESULTS 



1. Physical Parameters . 



a. Present Study . Values for water temperature, salinity, and 

 dissolved oxygen concentration for each station are presented in Table 5, 

 for November-December 1979, and in Table 6 for May 1980. Temperatures 

 during the November -December sampling ranged from 16.5 to 21.0 Celsius. 

 The lower temperatures were usually recorded in the colder, early morning 

 hours before the water became mixed and warmed by solar radiation. Bottom 

 temperatures at the deeper stations were generally slightly warmer than 

 surface temperatures. Variation of temperature was less during May with 

 values ranging from 24.0 to 26.0 Celsius. 



Salinity during the November-December sampling ranged from 32.5 to 

 35.5 parts per thousand, typical of open gulf waters not strongly in- 

 fluenced by coastal runoff. Salinities during May were slightly lower, 

 ranging from 29.0 to 32.0 parts per thousand. The extremely low values 

 recorded, 14.5 to 27.0 parts per thousand (Table 6), are believed to be 

 due to instrument malfunction. 



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