POPULATION STUDIES ON THE MINKE WHALE 167 



to changes in the seasonal catches and to the geographical distribution of the 

 catching activity. Since 1953, however, there has been a regular and marked 

 increase in the percentage of mature animals in the catches, from 30-8 in 

 1953 to 43*2 per cent in 1958, which most probably must be explained by 

 failing recruitment. Based upon known biological data for the minke whale, 

 it can be calculated that in an accumulated stock there will be about 60 per 

 cent sexually mature animals. During the period 1938-58, however, the 

 corresponding figure in the catches has been about 35*0 per cent. Season 

 after season during a span of more than twenty years, therefore, the sexually 

 immature animals have been more heavily taxed than the matures. 



REFERENCES 



JONSGARD, Age. (195 i). Studies on the little piked whale or minke whale {Balaeiwptera acuto- 



rostrata Lacepede). Norsk Hualfangsttid., 40, 80-96. 

 JONSGARD, Age. (1955). Development of the modern Norwegian small whale industry. Norsk 



Hvalfangsttid., 44, 697-718. 



