Myers et al.: Population growth rate of Gadus morhua 
771 
O) 
o 
<L> 
Cl 
(/} 
8 - 
15 
6 - 
18 
7 17 10 
4 - 
5 
14 19 
12 
2 
3 
1 
CO 
CD 
20 
2 - 
4 6 
9 
8 
0 - 
n r 
0 2 4 6 8 10 
Temperature (°C) 
Figure 9 
Rate of population growth (r m ) and slope at the origin (a) 
versus bottom temperature with estimated from the me- 
dian slope of the six observations with the lowest SSB. 
Populations are represented by numbers (See Table 1). 
desired levels of spawning biomass should not be 
expected for at least a decade of minimal mortality 
caused be fishing. 
Acknowledgments 
We thank the Northern Cod Science program for fi- 
nancial assistance. We thank N. Barrowman, K. 
Brander, J. Hutchings, J. Morgan, and S. Walde for 
helpful suggestions. 
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