ALASKA FISHERY AND FUR-SEAL, INDUSTRIES, 1920. 107 



above and illustrates the value of having a comparatively large aver- 

 age harem. The various proportions of massed areas where death 

 rates are high to scattered rocky areas where they are low have 

 been taken into consideration in arriving at the percentages. Also 

 of prime importance in this connection is the fact that the size of 

 the average harem in 1920 stands almost halfway between the figures 

 for 1915 and 1916. It is reasonable to suppose that the percentage 

 of dead pups would be governed thereby. 



In the early days of pelagic sealing, when large numbers of dead 

 pups were washed up by the surf, the impression was general that the 

 animals were drowned by storms. The matter entered into inter- 

 national negotiations when it was maintained b}^ the representatives 

 of the Government of Great Britain that this was a prime cause 

 of pup mortality. The fact that starvation was the cause of death as 

 a result of the mothers having been killed hj pelagic sealers was 

 thereby concealed. 



Dr. F. A. Lucas ^ has shown the subject in its true light and com- 

 mented on the fallacy of the much-llaunted ''deadly surf nip." By 

 actual autopsy he demonstrated that the number of 3'oung animals 

 drowned was insignificant. 



I personallv had never had an opportunity to make any observa- 

 tions on the subject until 1920, because violent storms had never 

 occurred at the proper season during my se\en years of work. But 

 this vear a iieavy gale from the southwest drove an enormous surf 

 into English Bay for three days during the latter part of July. It 

 was jjrecisely the time for deaths from drowning to occur, if such 

 ever occur. Some puj)s are then dabbling in the edge of the water, 

 while many others are young and weak. 



After tlie storm thorough search of the entire stretch of English 

 Bay beach was made, where over a tliousand had been counted at 

 one time during the days of pelagic sealing, but only 17 dead pups 

 were found there. Not one of these 17 animals had drowned, and 

 the majority of them were in an advanced stage of decomposition. 

 They were simply some of the usual dead which had been washed off 

 the rookerj'. 



Thus the findings of Dr. Lucas in this respect are comjiletely 

 confirmcfl. Drowning is the cause of a very insignificant portion of 

 the loss of fur seals. 



The intestinal parasite Uncinaria may be present among the pups 

 and may cause a few of the deaths recorded from year to year. 

 Autopsies were made in a few cases in 1920 where decomposition had 

 not proceeded too far. but in no instance could death be attributed 

 to this cause. It may be that the parasite is epidemic at periodical 

 intervals and will recur some time in the future. It is a point well 

 worth keeping in mind Ijy future investigators. 



In 1915 the presence of a considerable number of animals, both 

 young and adult, was noted and recorded which had the mange or 

 some skin affection allied to it to a greater or less degree. Each year 

 a few cases are seen, and they are usually marked by the presence 

 of small, round, hairless spots. These a re known in the fur trade by 



« Fur Seal InvestlRatlons, 1890-07, pt. 3, pp. 8.*i-84. 



