iV;r'"*.*?:> ;.*;:,:.; 





l?■i;■•^:''.•■^^• 



¥■■■:: ■.■••i ••.•:.■: 





Figure 2. — Suspension of spat collecting bags from chains to occupy different depths of the water column. 



station 10 (fig. 1) in the Tred Avon River 

 was dredged clear of oyster shells. When 

 stations were established and bags put 

 out, the plot was covered evenly with 3,524 

 liters of shells from the same source as 

 those in the bags. Five pairs of seasonal 

 bags were spaced evenly along the longer 

 center line of the plot. When the bags were 

 removed from the plot at the end of the 

 season, 10 equivalent volumes of loose bottom 

 shells were tonged from the area near the 

 paired bags. Spat counts on the two groups 

 were compared. 



THE WEEKLY SETTING OF OYSTERS IN 

 1961 and 1962 



Data from spat counts on weekly bags indi- 

 cated that conditions affecting oyster setting 

 in the Tred Avon River and Broad Creek were 

 different in 1961 and 1962. The set was very 

 light and sporadic in the Tred Avon River in 

 1961, but in 1962 the set was heavy during 

 the week of 30 July to 6 August (tables 1 and 

 2). Setting was much heavier in Broad Creek 

 than in Tred Avon River in both 1961 and 1962. 

 A peak occurred in 1961 between 17 July and 



