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Fishery Bulletin 104(3) 



-10 10 20 30 40 50 -20 -10 10 20 30 40 50 



Age 3 



• 10 10 20 30 40 50 -20 



10 10 20 30 40 50 



■20 -10 10 20 30 40 50 -20 -10 10 20 30 40 50 



Figure 1 



Results of the error analyses for the sandbar shark iCarcharhinus pluniheus) bioenergetics 

 model for ages 0-5 years, using the eleven parameters and distributions from Table 1 

 in 2000 Monte Carlo simulations. The horizontal axis is the percentage contribution of 

 the variable of interest to the variance in two model predictions: total seasonal prey 

 consumption in kg ^C^^^, black bars) and mean daily ration (<XBM/d, grey bars). Positive 

 values indicate that an increase in the parameter yields an increase in the model output, 

 and negative values indicate the opposite. See text for definitions of parameter abbreviations 

 along the y axix. 



of uncertainty in U, p. and Qk, were negligible for all 

 age classes. 



The Monte Carlo simulations predicted mean seasonal 

 energy consumption rates 11-15% higher than those 

 derived by using the static model. This elevation was 

 primarily due to the fact that SDA and fecal waste (F) 

 were allowed to comprise larger proportions of consump- 

 tion than in the static model runs. 



Discussion 



Comparison with previous results 



The mean daily rations for age-0 juvenile sandbar sharks 

 predicted from our bioenergetics model (2.17 '/rBM/d, 

 average M=2.2 kg) were higher than those previously 

 reported (1.32 %BM/d, M=1.9 kg, Medved et al., 1988; 



