104 THE FUR SEALS OF THE PRIBILOF ISLANDS. 
times, there being 19 drives, including 31 hauling grounds. In 1894 but 14 drives 
were made from 15 hauling grounds and in 1895 12 drives from an equal number 
of hauling grounds. The quota of 30,000 taken in 1896 was therefore affected in a 
measure by the nature of the killing of the seasons immediately preceding. The 
quota of 1897 is more nearly normal, but with the years immediately preceding it 
can not properly be compared. 
But if these matters have tended to confuse the data which might have led to a 
definite measure of decline, they do not obscure the fact of decline. This is every- 
where distinct and unmistakable. 
THE EVIDENCE OF DECLINE, 
ABANDONED GROUNDS. 
To the eye of the observer perhaps the most striking proof of decline is in the 
abandoned rookery spaces. On the rear and on either side of the present rookery 
areas are great tracts of ground which were once occupied, but which are now grass- 
grown. The evidence of former occupation is to be seen in the felt-like matting of 
hair over the surface, in the smooth condition of the stones, worn by the moving 
animals, and especially in the peculiar vegetation covering the area. These abandoned 
grounds are now covered with fine yellow grass, known as “seal grass,” which grows 
here and nowhere else. 
GRASS-GROWN AREAS. 
On some of the rookeries this grass-grown area shows three distinct stages. 
Close to the space at present occupied is a narrow belt of ground, which is still occasion- 
ally wandered over by the seals, and on which the grass is just beginning to spring up 
in spots protected by stones. This area shades imperceptibly into the absolutely 
bare region now regularly occupied. Behind this space lies an area of dark green 
grass, covering ground not now entered by the seals. The luxuriant growth of this 
grass is due to the fertilizing matter in the more recently abandoned grounds. 
Beyond this there is an extensive area of thinner yellowish grass of the same general 
character, its less vigorous growth probably connected with the impoverished condition 
of the soil. 
THEIR EXTENT. 
On several of the rookeries these three areas are clearly defined, and on all of 
them the yellow-grass area is very extensive. On the hauling ground of Lukanin 
rookery measurements made during the season of 1896 show the area of dark grass to 
be 16 feet in width and the area of yellow grass 64 feet. The area on which the grass 
is just starting is less definite, and can not be measured accurately. The outward 
line of the yellow-grass region marks the extreme limit of ground at any time occupied 
by the seals. The dark green area marks a stage of more recent abandonment. 
On certain hauling grounds the area of abandoned territory is anywhere from ten 
to twenty times the area at present occupied. This, however, does not mean that 
there has been a corresponding decrease in the bachelor herds. Observations show 
that a small band of bachelors can in a few days denude a large grass-grown area if 
they begin to wander and sleep upon it. Five or six times the present number of 
bachelors would doubtless denude all these areas. 
