36 



SEAL LIFE ON THE PRIBILOF ISLANDS. 



Census, hj/ harems, of a portion of Ueef rookery, below hi tiff north of Station 19, on July 15. 

 (The numbers indicate breeding females in each harem.] 



Whole number of breeding females 566 



Whole miiuber of harems 33 



Average females to harem 17 



Whole number of breeding females counted on Ketavie, Lukannon. 



Tolstoi, L:i;iOon, and Reef rookeries 7,479 



Whole uumticr of harems 434 



Average feiiialoa to harem 17+ 



RESTORATION OF THE ROOKERIES. 



With the number of breeding females in the Pribilof seal herd dimin- 

 ished to about 75,000 in July, IS!)."), and this number further reduced 

 by the pelagic loss of August and September (certainly not less than 

 30,000 females out of the catch of nearly 44,000), we have remaining a 

 very limited breeding stock, and yet, notwithstanding this circum- 

 stance, if absolute protection can be guaranteed to the seals without 

 delay and for a term of years, the stock is still large enough to insure 

 a comparatively rapid restoration of the rookeries. If there be no 

 further loss of females during the present winter by sealing on the 

 Northwest Coast, we may fully expect to find the rookeries in 1896 

 occupied by the present number of breeding females, about 45,000, 

 together with several thousand .3-year-old females that will then become 

 breeders. It is exceedingly dihicult to calculate the increase of 3-year- 

 old breeding females for that time, there being no record of the ])ropor- 

 tion of 2 and 3 year old females lost during the pelagic sealing of the 

 past two seasons. It is evident that the loss of over 50,000 pups in 

 1894-95 will result in a poor showing of breeding females in 1897-98. 

 Supposing, however, that the existing breeding females, with their 

 female progeny, were secured against destruction in future, the restora- 

 tion of the rookeries would be certain, and the rate of increase more 

 rapid from year to year. 



The following table showing the increase in seal life that would 

 naturally result from the complete protection of females is based upon 

 the natural-history facts that they breed annually from the third year 

 and produce both sexes in equal numbers. The loss from natural 

 causes, such as old age, injuries received on the rookeries, killer whales, 

 etc., is probably unimportant. 



Assuming a breeding class of 50,000 seals in 1896, there is shown an 

 increase to nearly half a million in ten years, while at the end of twenty 

 years the breeding females alone number over 6,500,000. The annual 

 increase of young males would be equal to the annual increase of young 

 females, or to half the breeding females. A very small proportion of 

 these being required for breeding purposes, this class would practically 

 be available annually as a surplus. Not only do seals breed early in 

 life, and with great regularity, but they return to their breeding 

 grounds with a faithfulness which demonstrates the security they feel 

 there. The seal rookeries of the Pribilof Islands can, therefore, unques- 

 tionably be restored, and at a known ratio of increase. These figures 

 may appear startling, but they are founded on simple natural-history 

 facts. 



