FISHERY BULLETIN: VOL. 80. NO. 2 



Table 3.— Monthly nutrient 1 values (mg/1) in southeast and southwest Biseayne Bay, Fla., locations (at 

 depth 0.3-1.0 m) (Dade County Department of Environmental Resources Management unpubl. data). 



'TOC = Total organic carbon, TAN 

 and in suspension. 

 2 Arsenicker Keys. 

 3 Sands Key. 



Total ammonia nitrogen. The term "total" refers to the amount present both in solution 



nutrients. Nutrient concentrations were consid- 

 erably higher in the southwest, especially am- 

 monia values. The water sample taken in April 

 1976 near Arsenicker Keys contained high total 

 organic carbon compared with the other samples 

 because of the proximity of an extensive man- 

 grove coastline and the presence of mangrove 

 detritus in the water. The two July 1976 water 

 samples from Sands Key were taken in a canal 

 and small lagoon inside the Key surrounded by 

 mangroves and connected to the bay. At low tide, 

 about two-thirds of the bottom muds of the lagoon 



Sch. Mar. Atmos. Sci., Prog. Rep. Fed. Water Qual. Admin., 

 198 p. 



4 Bader, R. G., and M. A. Roessler. 1971. An ecological 

 study of south Biseayne Bay and Card Sound, Florida. Rosen- 

 stiel Sch. Mar. Atmos. Sci., Univ. Miami. 



were exposed, the canal was rich in fish, and 

 wading birds fed in the flats at low tide. The 

 somewhat higher content of ammonia, nitrates, 

 and phosphates was due to decaying vegetation, 

 the exposed mud flats, animal concentrations, 

 and little flushing. Trace metals were present in 

 water samples from the southwest locations only 

 (Table 4). None were detected with standard 

 methods in water samples from the southeast 

 bay. Those pesticides either present or not de- 

 tected in the water in Black Creek during the 

 time of this study are shown in Table 5. None 

 were detected with standard methods in the 

 southeast bay. As in all the other southeast bay 

 samples, no pesticides or heavy metals were de- 

 tected in Sands Key samples. The junction of 

 Black Creek and Goulds Canals and the south- 



Table 4.— Potentially harmful trace metals (m g/1, total ) in southwest Biseayne Bay locations of Black Creek 

 and Mowry Canals, Fla., from May 1975 to May 1976 (USGS unpubl. data). 



'Natl Acad Sci., Natl. Acad Eng . Environ Stud Board (1972) 



274 



