Holme (1953) and Reish ( 1959) established that 

 1.5 mm and 1.4 mm mesh sieves recovered 90% of 

 the biomass from their samples, respectively. In 

 view of the importance of large forms in the Goose 

 Creek species composition, it is likely that the 10% 

 potential error described by Reish and Holme is 

 a conservative estimate. Since the purpose of 

 this investigation required an accurate estimate 

 of total standing crop, with special emphasis on 

 such commercially important species as Mercen- 

 aria and Mya, no attempt was made to separate 

 the "large" and "small" forms by using an arbi- 

 trary cut-off point, as the 0.2 g of Sanders (1956). 

 Thirty-eight stations and the once-a-month 

 sampling schedule produced over 400 separate 

 samples; this large A^ helped compensate for 

 statistical inaccuracies introduced by the pres- 

 ence of large forms. 



After a minimum of 1 yr of storage the speci- 

 mens were identified, weighed (blotted wet 

 weight), and dried at 40°C until uniform dry 

 weight was obtained. Pelecypods were shelled, but 

 crustaceans did not have their carapaces re- 

 moved, since many were too small for this 

 procedure to be performed with precision. Instead 

 the major weight factor of the shells, the car- 

 bonates, was substantially removed by the acidic 

 action of the unbuffered formaldehyde. The use 

 of an acidic medium to remove carbonates was 

 employed by Sanders (1956), Holme (1953), and 

 others. 



The data were expressed as number of organ- 

 isms/wet weight/dry weight (biomass) per m^ of 

 substratum, including all animals recovered, 

 according to the recommendation of Lee (1944). 



RESULTS 



Hydrography of Goose Creek 



The hydrographic data recorded below were 

 obtained from the reports of Hair (1968), Fazio 

 (1969), and Black (pers. comm.). Salinity was 

 measured by a portable Beckman salinometer 

 (Model RS 5-3),'* dissolved oxygen and tempera- 

 ture readings were taken with a portable oxygen 

 meter (Electronic Instruments Ltd. Model 15 A) 

 and pH was determined with a portable Orion 

 Instruments Specific Ion Meter (Model 401). Light 

 penetration was measured by a Secchi disc. 



••Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Service, NOAA. 



FISHERY BULLETIN: VOL. 72, NO. 2 



Water Temperature 



Average daily temperatures ranged from 25.5°C 

 to 0.5"C in the bay in 1967-68. The lowest indi- 

 vidual reading was -1.5°C on 11 January 1968 

 and the highest 29.0°C on 7 July 1967. In January, 

 February, and March, the bay was often covered 

 by ice. 



Salinity 



Maximum salinity values occurred in mid- 

 July to mid-October with a 1966-1968 high of 

 30. 12 /CO. Low salinities occurred from mid- 

 January to mid-April, with the 1966-68 low of 

 18.38 Vco recorded on 28 March 1968. 



Mean 1966-67 salinity in the bay proper (ex- 

 cluding the relatively less saline cut extending 

 from, the west shore) was 28.37 /^o . 



pH 



Average daily pH in Goose Creek ranged from 

 7.1 to 8.3 (excluding the somewhat more variable 

 western cut) in 1967 and 7.7-8.2 in 1966. The 

 highest individual value in 1967 was 8.6, occur- 

 ring during a phytoplankton bloom in Thyone 

 Cove, on 27 July 1967. The highest individual 

 value for 1966 was 9.0 during a dinoflagellate 

 bloom. 



Light Penetration 



Secchi disc readings were taken at weekly 

 intervals throughout the duration of the study. In 

 the bay itself the photic zone usually reached to 

 the bottom, since the total water column was 

 never more than 3.5 m. Virtually the entire bay 

 could be considered euphotic except during the 

 month in which the dredging took place, July 

 1967, when the minimum light penetration as 

 recorded by the Secchi disc was 0.4 m (Fazio, 

 1969). It appears, then, that light penetration 

 values were not substantially affected by the 

 introduction of suspended materials into the 

 water as the result of dredging. This is not 

 surprising in view of the shallow nature and 

 relatively rapid flushing time of the region of the 

 bay most severely affected by the dredging, the 

 eastern half. On the other hand, deposition of a 

 canopy of flocculent material on the leaves of the 

 Ruppia and the thalli of the Enteromorpha was 

 observed during and after the dredging process. 



450 



