CAUSES OF MORTALITY. 345 



them A's. D lies alone below his place with 1 cow. Other cows are scattered along 

 the muddy slide. A is asleep in his later place with 3 cows. E is gone altogether. 

 He was found thrown out of his position on July 21. F is in his place with 8 cows. 

 G is asleep away below ; 9 cows are scattered about where he belongs. X. has no cows 

 and is above A's old place. Y is gone altogether, unless a lone bull on the edge of the 

 clitt'is he. The green-necked cow with her pup is with A. It is not known whether 

 she has been absent since the 20th, when she was last seen. Two wet cows come in 

 slowly and creep up the slide, bleating very loudly, shaking their heads. There is 

 nothing going on at the water front. The few wet bulls are inactive. 



A cow selects a pup from D and repels 2 others. A large pup comes from above 

 down the wet slide to meet the mother, and they crawl slowly up to D. Other pups 

 look anxiously at each wet cow. 



JULY 28. 



Professor Thompson, Mr. Lucas, and Colonel Murray went to St. George on the 

 Corwin to make further investigation of the rookeries there. Mr. Macouu photographed 

 Polovina rookery. Dr. Jordan visited Gorbatch and the Reef. 



GORBATCH. 



A wet cow came in from the sea; her pup comes down to the lowest rock to meet 

 her. She sees me and goes right back into the water, leaving her hungry, crying pup 

 at the water's edge. A bull which seems young plunges into the water after the cow, 

 but he is not to be the master of the household. A pup is dead on the rocks above 

 the harem. It has a broken scalp with pus oo/dng out. Perhaps this pup belonged 

 to the cow shot some days ago on Zoltoi Sands while consorting with a half bull. The 

 harem is located only a short distance from this point. 



The cow which deserted her pup a few minutes ago bleats in the water, and the 

 pup answers, but will not go into the water. I retire and the cow comes in, going 

 high up on the rocks with her pup. When one passes a harem now the brown, rusty 

 cows leave for the water and the bull offers little resistance. It is chiefly the silvery 

 cows that remain. 



There are more than 50 pups paddling to day near the green striped bowlder that 

 looks like a watermelon. This is the place where pups were noticed in the water 

 yesterday for the first time. 



NATURAL CAUSES OF MORTALITY. 



The mortality from natural causes in 1,000 pups probably cannot exceed: ' 



(a) One killed by cows (overestimated). 



(/>) One killed or led oft' by foxes (overestimated). 



(c) Eight from being crushed to death by bulls while very young; this has caused 

 half the deaths so fur. 



(d) Two from being drowned. 



1 We allow the following notes on pup mortality to stand as written. It illustrates the difference 

 between qualitative and quantitative work. No actual count was then possible. A later count showed 

 that 70 to 80 in a thousand have been trampled while young, the other causes being all of trifling 

 importance. (This foot note, made iu 1896, must be again revised and corrected in light of the 

 discovery of the parasitic worm in 1897. ) 



00 / 

 UJ LI 



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