Zamora-Garcia et al.: Catch rate, length, and sex ratio of Mer/uccius productus in the Gulf of California 377 
species in the NGC, data-limited stock assessments could 
provide temporary reference points for management. 
The maximum size of Pacific hake in the NGC (108.8 cm 
TL) is at least 3-fold of that reported for Pacific hake in the 
southern Gulf of California and Baja California Sur (33.5 cm 
TL), and information about that stock is very limited 
(Mathews, 1975; Balart-Paez, 2005; Salinas-Mayoral, 2018). 
In the short term, focusing commercial fishing for Pacific 
hake on the NGC is a potential management strategy. 
As a precautionary measure, the specification that only 
vessels licensed to take Pacific hake can take individuals 
of this species in the NGC could help to eliminate fishing 
effort over the currently allowed level that is a result of 
illegal, or incidental, catch by other ships that fish in the 
NGC. In future research, particular attention must be set 
on examining the possible adverse effects of fishing over a 
reproductive aggregation. 
Acknowledgments 
The generous collaboration of the fishing companies of 
the hake fishery made this study possible. We thank the 
Posgrado en Ciencias del Mar y Limnologia and Consejo 
Nacional de Ciencia y Tecnologia for financial support and 
the Facultad de Ciencias del Mar for logistical support. 
This study is based on an observer program that is funded 
by the Environmental Defense Fund, the David and Lucile 
Packard Foundation, the alliance of the World Wildlife 
Fund and Carlos Slim Foundation, and the Walton Family 
Foundation. We are grateful to the observers who worked 
on board vessels in the fishery for Pacific hake, especially 
the late E. Estrada Aleman. Comments made by the 
reviewers are appreciated. 
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