Stark: Temporal and spatial variations in maturation and growth of female Gadus macrocephalus 



405 



800- 



600 



800 



600 



200 



X 10 



Age (years) 



Figure 6 



Total length (Lj., mm) at age of Pacific cod ^Gadus macrocephalus) 



females (O, --) and males (A, ) in (A) the Gulf of Alaska (S 



n = 375, (? n = 336) and (B) the Bering Sea ($ /! = 676, <? « = 684), based 

 on area-wide groundfish assessment surveys conducted by the National 

 Oceanic and Atmospheric Administration Alaska Fisheries Science 

 Center during 2003. 



cod than would have otherwise occurred. As a result, 

 the revised 2006 management plan increased the es- 

 timated spawning stock biomass by 80*?^ in the Gulf 

 of Alaska and by 10% in the eastern Bering Sea and 

 Aleutian Islands, over the 2005 plan estimates. These 

 increases offset declines in the estimated biomass of 

 Pacific cod over 2 years of age for the Gulf of Alaska 

 (4%) and for the eastern Bering Sea and Aleutian Is- 

 lands (19%) during the same period. Consequently, the 

 recommended over-fishing limit increased 51% in the 

 Gulf of Alaska and declined only 18% in the Bering Sea 

 and Aleutian Islands. 



Although temporal stability was found for Pacific cod 

 Agg and Lj,^^ estimates in the present study, maturity 



assessments should be conducted on a periodic basis in 

 the future to ensure that managers continue to receive 

 representative estimates of Pacific cod Agg and Lg^ and 

 timing of spawning, which are essential for rational 

 stock management. Maturity assessments would be 

 particularly important during periods of significant 

 change in climate or habitat. 



Acknowledgments 



Thanks to the following Alaska Fisheries Science 

 Center personnel for their contributions: D. Somer- 

 ton, G. Stauffer, R. Nelson, A. Hollowed, D. Nichol, 



