:.:^:-^*IP^***^ 



i-iiSKSa*:* 



^ ^1^*^ ~''i^r*«'-— fc 



Figure S. — Xortheni Boca Oiega Bay near Jobus Pass in l'Xi'2 showing first ba.vflll areas ( pliotograpli courtesy of 



Airflite, St. Petersburg, Fla.)- 



at Station PB-1 (Ho-. 10 and table 1). Stable and 

 relatively hig-h salinity in Boca Ciega Bay and 

 the temperate ov subtropical \vater temperature 

 favor tlie occurrence of a large number and diver- 

 sity of marine plants and animals (Gunter, 1961; 

 Kimie, 1964). 



In the sea, pH is generally near S and remains 

 stable unless atlected by al)normally liigli photo- 

 synthetic activity, rapid temperature change, or 

 anoxic conditions on the sea floor ( Skirrow, 1965) . 

 In Boca Ciega Bay the observed pH range of 7. '2 

 to 8.5 is normal for water of nearly oceanic salinity 

 (Park, Hood, and Odiiiii, 195S; Reid, 19(;i). 



Within any single sampling period pTI on the sur- 

 fai/e and bottom at each station varied no more 

 than one miit. 



OXYGEN 



Daytime concentrations of oxygen on the surface 

 and bottom of dredged and undredged stations 

 were at least 3.5 ml./l. in all seasons (table 1). In 

 mori' recent work, however, less than li nd./l. was 

 recorded in June and August from bottom water 

 at a dredged location in the central part of Boca 

 Ciega Bay near station PB— t (Dragovich et al., 

 I'.iCii;). These recent data show tliat oxygen is re- 



222 



f.S. FISH A.\l> WILDLIFE SERVICE 



