FUR-SEAL CENSUS, PRIBILOF ISLANDS, 1917. 99 



while the centrally located bulls regularly get 75 or more in many 

 cases. 



Back of the line where the last cows extend there are still more 

 bulls in position to which no cows come. These are called idle bulls. 

 Then there are roaming bands of younger males here and there back 

 of the idle bull lines. 



At the ends or in the middle of all the larger rookeries, paths are 

 left open in tlie breeding masses of seals for the young males, called 

 bachelors, to haul up to the rear of the rookeries on the plats, called 

 hauling grounds. The bulls never permit the bachelors to mingle 

 with the cows nor even to pass through the rookery elsewhere than 

 the regular runway. 



These bachelors are composed of males 2 to 6 years old. They 

 haul back on land to rest, sleep, and play for a week or more, then go 

 to sea to feed. Some old bulls also haul out on the hauling grounds, 

 especially those that have been severely injured on the rookeries. 

 Also, after August 1, an occasional yearhng comes out on the hauling 

 grounds. 



The yearlings, as a class, arrive at the islands after August 15. 

 They scout the margins of the rookeries only and play with the pups, 

 which are then just learning to swim. The yearlings are very small 

 and thin as a rule; in fact, many weigh less than when they left the 

 islands in the previous November. There is considerable variation 

 in the coloration of all classes and ages of seals, but the yearlings do 

 not differ as a rule from the 2-year-olds in this respect. Females and 

 males are alike externally, and together play with the pups. 



After August 1 the rigid harem discipline is relaxed, the pups begin 

 to "pod" back of the rookeries as well as swim, and the cows follow 

 them. Then by August 15 there is a general prowling over the rook- 

 eries by young bulls and many cows resort to the hauling grounds to 

 play and sleep. The breeding heat has then practically passed for 

 males as well as females. Some 2-year-old cows only remain to be 

 impregnated, and these are served by the yoimger bulls roaming over 

 the breeding grounds. The 2-year-old cows arrive late in the breed- 

 ing season after most of the others have given birth to their pups. 



The hauling-ground seals are the important ones commercially. 

 They are practically all males in June and July. They occupy areas 

 of their own and can be driven like sheep to a selected spot for killing 

 without any disturbance of the breeding classes. The older ages 

 come first in the spring, and killings can usually be made in the latter 

 part of May. The 2-year-olds, the smallest of the lot, do not arrive 

 in large numbers until after July 1 . 



THE PUPS. 



The count of pups used to begin on July 26. This was attended 

 with some difficmty owing to the presence of buUs, cows in heat, and 

 newborn young, but no serious obstacles were encountered. In 1916 

 the lar^e influx of bulls made it necessary to defer some of the count- 

 ing as late as August 15. This is objectionable because some of the 

 pups are swimming on that date and the number in the ^\ater must 

 be estimated. It is highly desirable, therefore, to complete all pup 

 counting before that date. 



