320 BULLETIN OF THE BUREAU OF FISHERIES. 
were about 100 seals remaining. It is believed that these will be protected by 
Japan, to which country they belong. The seal inhabiting Robbin Island and 
the Kuril Archipelago is now known as Callorhinus curilensts. 
The only important strongholds of the diminishing northern fur seals 
to-day are the Pribilof and Commander islands, in Bering Sea. The species 
established on the Commander Islands is Callorhinus ursinus, while that breed- 
ing on the Pribilofs is Callorhinus alascanus. Although the two species breed 
upon islands lying in the same latitude and less than 1,000 miles apart, there is 
no commingling. The former migrates southwestward in winter along the 
Asiatic coast, while the latter migrates southeastward along the American coast. 
Upon the discovery of the fur-seal islands of Bering Sea, more than a century 
ago, seals were found in great multitudes. For many years they were killed 
indiscriminately, but the Russian Government finally took charge of them and 
directed the fisheries in such a way that they were regularly productive. The 
Pribilof Islands in the twenty years after the accession of Alaska yielded more 
than $7,000,000, the price paid for the entire District. About twenty-five 
years ago the practice of pelagic sealing—the killing of seals in the open sea— 
developed into an extensive industry, since which time the supply of seals has 
steadily decreased. 
Although during the winter months the fur-seal herds migrate into the 
Pacific Ocean, they are in summer located on their anciently established breeding 
places in Bering Sea. The fishery is conducted under government super- 
vision, and a certain number of seals may be killed on the islands, selection 
being made in accordance with the natural habits of the animals. Fur seals are 
highly polygamous, and the rookery communities are divided up into harems. 
The males arrive at the islands and fight furiously for the possession of territory. 
The females, arriving soon after the males have established themselves, are 
divided up among them, in numbers varying from a dozen to a hundred to each 
male in extreme cases. This arrival occurs in June, and the young are born 
the last days of June or in the early part of July. The young seals remain with 
their mothers until the latter part of August. The seal herd lingers about the 
islands until late in the fall, when the annual movement into the Pacific Ocean 
takes place. 
The highly polygamous habit of the fur seals naturally results in a large 
surplus of males, which surplus, when the rookeries were in their best condition, 
amounted to about 100,000 immature males a year on the Pribilofs and over 
35,000 a year on the Commanders. These half-grown males herd by themselves, 
on so-called “‘ hauling grounds” adjacent to each breeding rookery, and it is from 
them that the annual catch on the islands has always been made. The seals 
are quietly surrounded, and without difficulty are driven inland, entirely away 
