Table 13. Pearson correlation coefficients (r) for significant (p < 0.05) zooplankton 

 relationships in East Bay, Apalachicola Bay, and coastal areas (Edmisten 1979). 



Variable 



East Bay 



Apalachicola Bay 



Coastal areas 



Temperature vs. 

 Acarti a tonsa 

 Total zooplankton 

 Zooplankton biomass 



Salinity vs. 

 Acarti a tonsa 

 % Acarti a tonsa 

 Total zooplankton 

 Zooplankton biomass 

 Zooplankton diversity 



0.45 

 0.50a 



0.45 

 0.58 

 0.58 



-0.30 

 0.31 

 0.40 

 0.51 



0.463 



^Significant at p ' 0.10. 



less than ?0% of the overall abundance. 

 The evenness factor is hiqher in the more 

 stable marine environment with increased 

 representation by cladocerans, decapod 

 larvae, and other cooepods (i.e., Temora 

 turhinata , Paracl inus parvus , P_. 

 crassirostris , Oithona nanlT ) (Tdmisten 

 1<379) . Zooplankton biomass in coastal 

 waters is correlated with temperature (r = 

 0.46). 



Zooplankton in Apalachicola Bav has 

 characteristics of both the inshore and 

 offshore components (Edmisten 1979). 

 Overall numerical abundance was highest in 

 Apalachicola Bay (Figure ?fi). Numbers of 

 and total zooplankton 

 biomass follow general 

 of water temperature, 

 the spatial distribution 



any 



Acarti a tonsa 



abundance and 



seasonal trends 



Salinity affects 



of zooplankton in Apalachicola Bay at 



given time. Salinity increases appear to 

 be associated with decreased relative 

 abundance of Acarti a tonsa . At low 

 salinities, lower numbers of Acarti a are 

 taken although this species still comorise 

 a hiqher percentage of the overall zoo- 

 Dlankton assemblage at such times. Thus, 

 while temperature influences overall 

 trends of abundance through time, salinity 

 is associated with the spatial 

 distribution and relative abundances of 

 zooplankton in Apalachicola Bay at any 

 given time. 



4.?. LARVAL FISHES 



Planktonic fish larvae, derived from 

 either demersal or planktonic eggs, are 

 common among various marine teleost 

 species. While it is well known that 

 estuaries have relatively high levels of 

 phytoplankton productivity and that such 

 levels are necessary for feeding 

 aggregations of zooplankton (Mann 1982), 

 the relationship o-f such high productivity 

 to developing stages of marine fishes is 

 not quite as well known. Lasker (1975) 

 has shown that larvae of the northern 

 anchovy ( Engraul is mordax ) feed on 

 phytoolankton and that there is a direct 

 association between feeding activity and 

 phytoplankton concentration. Thus, there 

 may be close relationships between the 

 highly oroductive inshore waters of the 

 Gulf and develooing stages of various 

 teleost fishes. 



The relatively high numbers of 

 ichthyoplankton in the Apalachicola 

 estuary indicate the importance of this 

 system as a nursery for fishes. The most 

 abundant planktonic form is the bay 

 anchovy ( Anchoa mitchil li ), which accounts 

 for 92% of the eggs and 7S% of the larvae 

 taken during a year-long survey (Tables 

 14, 15; Blanchet 1978). Other relatively 

 abundant larvae include silversides 



46 



