242 EIGHTH PACIFIC SCIENCE CONGRESS 



and Corral. Only the hake is affected by the present trawl fishery, which 

 is carried out between Coquimbo in the north and Talcahuano in the 

 south. 



Owing to the rocky nature of the Chilean continental shelf it is only 

 in very small, minute areas of the large coastal region between Coquimbo 

 and Talcahuano that trawling could be carried out. This fact alone 

 makes it rather improbable that overfishing could occur through the 

 present trawl fishery. 



The hake was found from ca. 20 to ca. 150 m. depth and in greatest 

 quantities between 50 and 150 m. In deeper waters deeper than 150 m., 

 the trawl could not be operated. The fact that the catch was far 

 smaller between 125-150 m. than between 50 and 125 m. shows, however, 

 that greater concentrations of hake at the bottom in deeper water can 

 hardly be expected. 



The biological study of the hake carried out in connection with 

 the experimental trawling showed the following main results: 



Reproduction 



The spawning season is very extended, lasting from the beginning 

 of October to the end of April. The material further indicated that 

 the long spawning season has two maxima, one bigger in October- 

 January and a smaller in April-May. 



The length upon attaining maturity for the first time varies some- 

 what from south to north. Fifty per cent were found mature in the 

 southern area at a length of 37 cm, in the northern area already at 30 

 cm. The males grow mature at a somewhat smaller size than the fe- 

 males. 



Growth 



Owing to a great number of individuals with accessory rings in 

 scales and otoliths, these gave only little help for the determination of 

 growth. However, measurements of large numbers showed distinct 

 peaks of the length curves and thus the length at the close of the first 

 to fourth year could be determined as follows: 



1 year old— 16cm 



2 years old— 27cm 



3 years old— 38cm 



4 years old— 47cm 



The growth of the females is only a little faster than that of the 

 males, the 3-year old females being 3-4 cm bigger than the males. Fur- 

 ther, the females grow to a far bigger size than the males, and probably 

 live longer. No males bigger than 52 cm were found; females, however, 



