6 FUR-SEAL HERD OF ALASKA. 



seals are born as early as June 16-24 — a few are born as late as 

 August 1-5, annually — but these are the natural exceptions to the 

 rule of their lives. The fact remains that the breeding of these seals 

 is all begun and finished practically between July 4-20 annually — i. e., 

 nine-tenths of it. 



IV. This fact determined, then it becomes clear to the investigator 

 that the breeding males which serve these breeding cows in that short 

 period, annually, and only then, should be the very finest of the 

 species, and — 



(a) That they should not be overtaxed by havmg too many cows 

 in their harems at that period aforesaid, and — 



(b) That this natural selection ordered by their law of life, which 

 enables only the finest of their kind to get into the rookeries as sires, 

 should never be interfered with by man — 



(c) Who himself can not make that selection, as he can of the best 

 bulls, rams, stallions, and boars for his herds and flocks in domes- 

 tication. 



V. To make this natural selection of the very finest sires for the 

 herd, these seals are born equal m number, males and females. The 

 male becomes mature and begins to breed when 6 years old — never 

 any earlier, and — 



(a) The female becomes mature and receives her first impregnation 

 as a "nubile" on the rookery when she is 2 years old. This — 



(h) Brmgs the female in as a breeder and requiring service four 

 years ahead of the male; and that — 



(c) Seems to make the natural life of the male from 15 to 18 years 

 and that of the female less, or from 10 to 12 years (reasoning by 

 analogy) . 



VI. The breeding males arrive on the rooker}^ grounds from three to 

 six weeks in advance of the females ; their habit is to locate thereon, 

 at intervals of 7 to 10 feet apart; these locations being made by 

 those bulls which can successfully fight for and hold their location 

 when obtained, and — 



(a) This fighting between the bulls, which is done by them three 

 to six weeks before the cows come, eliminates all of the weaker or 

 nerveless bulls before the breeding begins, and — 



(h) So secures for the cows only the very finest sires for the race, 

 without any injury to the females or the pups during the breeding 

 season, since — 



(c) This fighting for those harem stations aforesaid entirely sub- 

 sides when the cows begin to haul out; and — 



(d) This location of the breedmg bulls in a normal and natural 

 state brings to each bull about 15 or 20 cows to serve, on an average, 

 thi-oughout the whole rookery (a few bulls will have harems of 40 or 

 50 and a few will only have 4 or 5, perhaps, but the natural normal 

 average in 1874 was about 20 cows to a bull on the big rookeries). 



VII. Any disturbance or interference with this natural order and 

 adjustment of these laws of breeding as set forth above will throw 

 the same out of balance and effect, and thus cause the birth rate 

 on the rookeries to become less and less annually, as long as this 

 interference is continued, up to the point of complete extinction of 

 the species, if it is not discontinued. 



With the above statements of fact clearly m mind, when we turn 

 to view the conditions of the Pribilof fur seal herd as it was plain to 



