DURBIN and DURBIN: ASSIMILATION EFFICIENCY OK ATLANTIC MENHADEN 



Table 3. — Feces elimination and nitiogen excretion of a school of 12 Atlantic menhaden, in relation to a 7-h period of 

 feeding on the diatom D;7v7(^;?! hn/^htuvlli .whereUme t„ = the beginning. /„^^ = the midpoint, and /, the end of the feeding 

 period. At to.-,, 50' i of the ration has been ingested. Column numbers, in parentheses, are for text reference. 



1.0 



5 



>^ 



o» 



6 



UJ 

 < 



< 



z 



LU 



o 

 o 



CO 



0.01 



1.0 



0.1 



0.01 



0.1 



0.01 



0.1 



- 0.01 



aooi 



0900 1500 2100 0300 



TIME, hr 



0900 



Figure l. — Silicon elimination rate (circles! of a school of 12 

 Brevoortia fyra^nus, during and after a 7-h (0800-1500 h) period 

 of feeding on the diatom Ditylum hrightwelli. Curve represent- 

 ing the calculated stomach evacuation rate is fitted to the feces 

 elimination data; further explanation in text. Numbers refer to 



50 

 100 



UJ 



z 

 o 



p 50 

 3 100 



2 



SOL-r 

 20p 



5:= 



o: ._ 

 a. X 



CARBON 



< -a 



UJ ? 



u. t 







1200 



v^r\ 



1800 2400 0600 



TIM E , hours 



1200 



Figure 2. — Experiment 4 (high ration. Table 4). Changes in the 

 fecal elimination rate of 12 Brevoortia tyrannus, and carbon, 

 nitrogen, and caloric assimilation efficiency during and after a 

 7-h period of feeding (dark line on the x-axis) on Ditylum 

 brightwelli. 



■t 50 



S ° 100 



NITROGEN 



-T r- 



3 tioop 



CARBON 



O Cr .Q 





^411 



1800 



I ' I ' I ( I 1 



2400 0600 



TIME, hours 



FIGURE 3.— Experiment 7 (low ration. Table 4). Symbols are as 



in Figure 2. 



the elapsed time (minutes) in the feeding period when food cor- 

 responding to the fecal sample was ingested. 



605 



