1899] THE HABITS OF THE NORTHERN FUR SEAL 27 
course of driving the seals, by which this bull had been driven into 
the sea (as I have seen many others during the course of a drive on 
the very same ground), and had not returned for some hours. But 
later in the season on the Pribilofs, on the little undisturbed rookery of 
Ardiguen, there was under the observation of our whole party a bull 
who, after having held his own place valiantly before all comers 
throughout the season, at length retired to the sea for rest and food. 
But to our surprise we saw him returning fat and sleek after a few 
days’ absence, and during the rest of my stay on the island he con- 
tinued his assiduous attentions to his now attenuated harem, varied only 
by occasional visits to the sea. It appears, then, that there is a good 
deal more latitude and deviation from their habits on the part of bulls 
than one would have supposed from reading the earlier accounts, and 
there can be no question that some of the bulls which frequent the 
rookeries of the Commander Islands come and go to and from the sea 
and their harems even at the height of the breeding-season, but that 
others (as noticed at the Pribilof Islands) only assume these wandering 
habits at or near the close of that period. I never saw a bull that I 
was certain was a really old one behave in this irregular fashion, and 
the old yellow-looking bulls of the central massed portions of the 
rookery never left their places even for an instant, so far as I could 
see. It may be, therefore, that the irregularity occurs only among 
the younger bulls, and is due to the system of management of the 
rookeries, whereby the number of spare bulls has been diminished, so 
that young animals have no difficulty in gaining harems for themselves 
at_an age when their strength would certainly have been insufficient to 
have enabled them to do so in a state of nature. At all events, such 
wandering habits are normally those of the larger bachelors and half- 
bulls, who, when unable to gain access to the harems, pass a restless life 
on their outskirts, varied with occasional—in the case of the younger 
animals frequent—visits to the sea. To these habits the two bulls of 
the little South rookery of Bering’s Island reverted at the end of July 
(1897), first becoming restless and moving about a good deal before 
they left the rookery for good. 
On the 13th July, on which date the North rookery was visited by 
Dr. Stejneger, Professor D’Arcy W. Thompson, and others, it was found 
that there had been a marked increase in the number of the seals, both 
in the case of the females and, what struck me more, in that of the bulls. 
The western section, which had never contained more than six bulls 
and 179 cows on any previous occasion on which we had visited it, 
now included a number of cows which was variously estimated at from 
500 to 700 individuals. With these, from seven to ten bulls were 
noticed by the various observers. The area occupied by the seals had 
greatly increased, and the harems which had been previously under 
observation were now indistinguishable ; the places of the two bulls were, 
however, occupied, if not by the same animals, by similar or identical 
