FISHERY BULLETIN: VOL. 80. NO. 4 



tures along the shore especially in the summer 

 months (July-September). 



Salinity varied more than temperature (Fig. 3) 

 due to rainfall and periodic runoff from sur- 

 rounding urban areas. In general all stations had 

 low salinities during January through March 

 1978, a period of heavy rainfall. After May 1978, 

 salinities remained high (between 25 and 32 ppt) 

 with decreases in June 1978 (stations 1 and 3, un- 

 known cause), September 1978 (all stations due 

 to heavy rainfall), and January 1979 (station 3 

 due to rainfall). Panne salinities at station 1 were 

 consistently low (usually <6 ppt) indicating a 

 constant freshwater input. The pannes at sta- 

 tions 2 and 3, however, usually had salinities 

 equal to or higher than the alongshore area due 

 to evaporation. 



Total Catch 



Sampling during the 13-mo period yielded 

 55,561 individuals of 32 species that weighed a 

 total of 103.5 kg (Table 2). 



Station 1 



40 

 30 

 20 

 10 



Station 3 



i i i 1 i 1 1 1 i 1 1 1 



J78FMAMJJ ASONDJ79 



Months 



Figure 3.— Month-to-month variation (January 1978-Janu- 

 ary 1979) in salinity (ppt) for the alongshore area and panne 

 at each of the three sampling stations. (* = panne dried-up.) 



Atherinops affinis greatly predominated in 

 numbers (76.7%) and biomass (79.9%). Fundulus 

 parvipinnis ranked second in both numbers 

 (12.1%) and biomass (7.6%), followed in order by 

 Gambusia affinis (5.5% numbers), Clevelandia 

 ios (2.4% numbers), and Anchoa com pressa (1.2% 

 numbers). These five species accounted for 98% 

 of the total number of individuals and 96% of the 

 total biomass (Table 2). The skewed distribution 

 of number of individuals among species was re- 

 flected in the relatively low overall H' diversity 

 values of 0.89 for numbers (H' N ) and 0.84 for bio- 

 mass {H'h). The vast majority of individuals of 

 most species were either young-of-the-year or 

 juveniles. 



Station 1— A total of 13,859 individuals repre- 

 senting 19 species was collected during the year. 

 The catch totaled 22.7 kg. All three of these totals 

 were the lowest of those from the three stations. 

 Overall H' diversity for numbers was 1.17 and 

 for biomass, 0.89. Atherinops affinis ranked first 

 in numbers (55.2%) and biomass (76.7%) but was 

 less abundant here than at stations 2 and 3. Gam- 

 busia affinis (20.6%) and Fundulus parvipinnis 

 (19.1%) were common at this station especially in 

 the panne. 



Station 2— The greatest number of individuals 

 (24,813) and biomass (42.9 kg) were collected at 

 this site. Although 27 species were captured, 

 over 90% of these individuals were from one spe- 

 cies, Atherinops affinis. The large number of 

 attached eggs and small (<20 mm) fish caught in 

 July (52% of all A. affinis) indicated that this area 

 was a breeding site for A. affinis. Fundulus par- 

 vipinnis (4.4%) was second in numerical rank. H' 

 for numbers (0.49) and biomass (0.70) were low. 



Station 3— A total of 16,889 fishes belonging to 

 23 species were obtained at this station. Ather- 

 inops affinis made up 74.4% of the individuals 

 and 78.8% of the 37.9 kg total biomass. Other im- 

 portant species in order of decreasing numerical 

 abundance were Fundulus parvipinnis (17.6%), 

 Clevelandia ios (3.4%), Cymatogaster aggregata 

 (1.3%), and Anchoa compressor (1.3%). Overall, Hh 

 and H'u were 0.87 and 0.85, respectively. 



Cumulative Species Curves 



Cumulative species curves from February and 

 June (Fig. 4) reached an asymptote before 20 

 samples (about 66% of total samples), indicating 



774 



