i64 Age jonsgArd 



season in July, will delay the taking of some calves up to three weeks. 

 Comparing the sizes of calves caught before the ist July, before and after the 

 introduction of the close season in 1950, it looks as if the closure to some 

 degree may have influenced the taking of smaller calves, but the close season 

 alone cannot explain the total decrease in the taking of the smallest calves. 



4. The smaller calves have been exploited more severely than the bigger ones 

 This may be the case, because recently weaned calves usually seek the whale 

 catcher and they are, therefore, more easily caught. Since almost all the 

 calves are born between November and March with the bulk of births in 

 January, the smallest calves would be relatively scarce in the whaling season. 

 If, therefore, the number of calves decreases considerably, the total catch of 

 calves cannot be kept at the same level unless all sizes of calves are caught 

 more indiscriminately than before. 



There is a good correspondence between increased catch of pregnant 

 females and decreased number of smaller calves in the catches. 



CHANGES IN THE RELATIVE NUMBERS OF SEXUALLY 



IMMATURE AND MATURE ANIMALS IN THE CAICHES 



From biological evidence we may assume that as an average, males over 22 ft 



and females over 24 ft in length are sexually mature. Our material has been 



divided into immature and mature animals accordingly. 



50 55 1958 



Seasons 



Fig. 4. — Percentage of mature minke whales in the catches. 



