CAUSES OF CHANGES IN HABITS, ETC. 399 



Curing ttiis and the following years, resulted iu considerably 

 delaying the time of their impregnation. Owing to the mild 

 weather late in autumn, the mothers of these late pups were 

 able to stay until their young were old enough and strong 

 enough to insure their safety. 



" The decrease in the number of breeding males may be con- 

 sidered as having reached its minimum in 187G. In 1877, the 

 last season I spent at the islands, there was an evident increase 

 in the number of this class. A review of the different classes 

 will now assist us in drawing our conclusions. The reserves 

 and beachmasters belong to a single class, the only difference 

 being that those which get on shore first and hold a place for 

 a family are denominated beachmasters, while those of the same 

 class that arrive too late for this purpose are termed reserves. 

 In 1809 the beachmasters were numerous enough to occupy the 

 breeding-ground in the proportion of one to the square rod, 

 leaving a surplus or reserve of double this number, or three 

 times as many as could find space on the breeding- ground. 

 There being so large an excess of males of breeding age, they 

 crowded each other to the extent of leaving only fighting-room, 

 averaging one beachmaster to seven females. The beachmas- 

 ters were continually fighting for the possession of the females, 

 often killing each other in their struggles, while many more be- 

 came so crippled as to have to retire from the breeding-grounds, 

 so that during the season the injured and exhausted amounted 

 to fully 30 per cent. This condition continued until the ef- 

 fect of the excessive killing iu 1865 became apparent, resulting 

 in the reduction of the reserves from natural causes. Those 

 already old died out. and the products of 1866 and 1867 being- 

 reduced by overkilling in 1868, fewer were left to mature to 

 make up for the natural loss. Consequently, in 1870, or be- 

 fore the Alaska Commercial Company began to take the ani- 

 mals for their skins, this class had perceptibly decreased. Dur- 

 ing the succeeding three years, nearly all of the half-bulls being- 

 killed, there was no new stock to replace the natural decrease 

 from old age and exhaustion, nor many half-bulls to assist in the 

 duties of reproduction. This rendered the season of service for 

 the old Seals more protracted. In three years, or by 187:>, the 

 old reserves had become so reduced in number that when the 

 Tookeries were fully occupied there were only half as many 

 beachmasters there as formerly, or only one to two square rods 

 of area, while each beachmaster had on the average about fifteen 



