114 U. S. BUREAU OP FISHERIES. 



to every rookery. The figure must be based largely upon yearly 

 observations of rookery life. 



The number of pups on St. George Island in 1922 is but little more 

 than was estimated in 1921, the increase being 0.89 per cent. In 

 1921 the per cent gain was estimated to be 10.47, which was probably 

 a little high. The total count of 1922 for both islands showed an 

 increase of 5.24 per cent over the estimated figures of 1921. 



That the number of dead pups on the rookeries was small was 

 noticed early. In 1921 the percentage of dead pups was estimated 

 to be 2.48 for both islands. In 1922 it dropped to 1.73, derived from 

 actual counts. It is not believed that the 1921 figure was too high. 

 From the top of the counting tower near rock 17 on Reef rookery in 

 1921 there were counted 22 dead pups just before the census of 

 harems was taken. In 1922 at approximately the same time only 8 

 dead pups could be seen from the same tower. Of the 22 rookeries 

 on both islands 9 show small increases and 13 show decreases in the 

 percentage of dead pups. On Zapadni Eeef rookery, St. Paul 

 Island, the percentage of dead dropped from 3.19 (actual count) 

 to 0.8 (actual count). On Gorbatch rookery it dropped from an 

 estimated percentage of 2.74 to an actual percentage of 0.86. It is 

 believed that the absence of rain and the constant temperature dur- 

 ing June and the greater part of July tended to reduce the death 

 rate of pups on the rookeries. The increase in the average harem 

 also tended to decrease the percentage of dead pups. 



COWS. 



The table showing the distribution of pups will show the number 

 of cows on the various rookeries, since the number of breeding cows 

 is the same as the number of pups. The various percentages of in- 

 crease or decrease of total pups will also apply to the cows. In all 

 90 dead cows were found during the pup count. This is a decrease 

 of 29 from the number estimated in 1921. It is a little less than 0.05 

 of 1 per cent of the total number. 



BRANDED SEALS. 



Cows that as pups were branded with a single bar across the back 

 between the years 1900 and 1903 continue to reappear on the rook- 

 eries of St. George Island. Four animals of this series were ob- 

 served and each was raising a pup. These animals were at least 

 19 years old. When it is understood that seals born in 1903 passed 

 through eight years of pelagic sealing, the continued presence of 

 these cows is all the more remarkable. 



Several cows bearing the 1912 brand appeared on St. George 

 Island, and probably some were present on St. Paul, although none 

 was observed there. Four bulls branded as pups in 1912 with the 

 T-brand on the top of the head were also seen on St. George Island, 

 each in charge of a harem. 



HAREM AND IDLE BULLS. 



The count of harem and idle bulls was made on St. Paul Island 

 from July 16 to 20 and on St. George Island from July 22 to 23. 

 The harems had begun to break up before the count was entirely 



