58 
Fishery Bulletin 116(1) 
Acknowledgments 
We thank observers who helped us with the collection 
and processing of samples. We also thank B. L. Liu, for 
providing the squid age data. Y. Gong and Y. K. Li were 
supported by the National Natural Science Foundation 
of China (#41541042), the Natural Science Foundation 
of Shanghai (#17ZR1413000), and the Shanghai Lead¬ 
ing Academic Discipline Project (Fisheries Discipline). 
The senior author and X. Chen contributed equally to 
this work. 
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