PRESENT KNOWLEDGE OF THE PACIFIC WALRUS 
Certain aspects of the walruses' biology, and of human use 
patterns, are fairly well understood. Other aspects, such as current 
population status, require further studies and will be discussed in a 
subsequent section. 
Description 
The general appearance of the Pacific walrus is well known 
(Figure 2). The prominent tusks, which are modified canine teeth, are 
perhaps its most obvious distinguishing feature. The tusks of males may 
be up to 30 inches long and may weigh 9 pounds or more; tusks of females 
are somewhat shorter, slenderer, and lighter in weight. Large bull wal- 
ruses may weigh more than 14 tons, /three from the Walrus Islands weighed 
3,432 pounds, 3,203 pounds, and 2,895 pounds, respectively, (Kenyon, 
1958a)/ and are up to 12 feet long. Females are about two-thirds as 
large as males. 
Migrations and Habitat 
Both Brooks (1954) and Fay (1955) describe the migration of the 
Pacific walrus. The descriptions are very similar: the general pattern 
is one of movement northward in the spring and early summer and southward 
during the fall and winter. The animals follow the southern edge of the 
ice pack and thus always have an area to haul out on immediately above a 
rich source of food. Certain groups, usually of males, haul out on shore, 
as in the Walrus Islands in Bristol Bayon the American side and at two 
or three hauling grounds on the Chukotsk Peninsula on the Siberian side. 
Occasionally, especially in the course of southward migration in the 
fall, walruses of both sexes and all ages haul out on land. The Diomede 
Islands in the Bering Strait are among the places frequented at this time 
of year. 
During the months of January and February, and even until 
mid-March, most of the walrus population can be found loosely aggregated 
in a broad undulating band extending across Bering Sea from Bristol Bay 
on the Alaskan side to the Gulf of Anadyr on the Siberian side. The wal- 
ruses occupy an area which is perhaps 150 to 200 miles wide in January 
but slowly increases in width until it may reach 300 miles by late 
February. Within this zone, walruses are concentrated on the north sides 
of islands and peninsulas and at the southern edge of the more or less 
solid ice pack. 
During March the pattern remains much the same but there is a 
definite tendency for some small herds to move northward, especially in 
the Strait of Anadyr. Some walruses also are reported north of 
St. Lawrence Island by pilots flying from Gambell on St. Lawrence Island 
to Nome on the Seward Peninsula. 
3/ Place names mentioned in the text are shown in figure 1, page 3. 
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