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BULLETIN OF THE BUREAU OF FISHERIES 
In Shuyak Strait the catch commenced to decline in 1926 and had fallen to 
practically nothing by 1928. The presence of fish of many year classes in the catch 
indicates that this decrease can not be assigned to the passage of dominant year 
classes. The decrease in abundance has been so rapid and so great as to cause one 
to question whether it can be due to depletion, but the concentration of large quan- 
tities of gear in the very restricted area fished makes it appear quite probable that 
such has been the cause. 
SUMMARY 
The following brief summary is given of the main conclusions reached in this 
paper: 
BIOLOGY 
1. The Pacific herring is very closely related to the Atlantic herring. 
2. Herring of 1 and 2 years of age occur close inshore. In the summer months 
thej" mingle only slightly with the schools of older fish. 
3. The schools of mature herring disappear after spawning and reappear in 
summer. They approach the shore in the fall and remain in close proximity thereto 
until spawning time. 
4. The herring are naturally smaller in the southern part of their range and 
increase in size toward the north and west, the largest being found along the Alaska 
Peninsula and in the Aleutian Islands. 
5. The existence of separate populations of herring has been demonstrated in 
California, southern British Columbia, Craig, Chatham Strait, Stephens Passage, 
Prince William Sound, Kachemak Bay-Shuyak Strait, Shearwater Bay-Old Harbor, 
Chignik, Shumagin Islands, Unalaska, and Golovin Bay. Dogfish Bay herring may 
also be a distinct stock but more data are needed to confirm this. 
6. The herring spawn later in the northern and western portions of their range 
than in the southern. 
7. In Kachemak Bay, central Alaska, 52 per cent of the 3-year olds, 83 per cent 
of the 4-year olds, and all of the 5-year olds were mature. 
8. In Stephens Passage, southeastern Alaska, 84 per cent of the 3-year olds and 
all of the 4 and 5 year olds were mature. 
9. The age of the Pacific herring can be determined with a fair degree of accuracy 
from the scales. 
10. The differences in rate of growth are marked. At 6 years of age the Unalaska 
herring are 6.5 centimeters longer and 2.8 times heavier than* Stephens Passage 
herring. 
11. The date of attainment or loss of sufficient fatness for pickling will vary at 
least two weeks in different years. 
12. The condition (or fatness) attained by any certain date may vary considerably 
between adjacent localities. 
13. The maximum condition attained will varj^ considerably from year to year. 
CONDITION OF THE FISHERY 
1. Owing to the short periods during which samples are obtainable from any one 
locality in central Alaska, the proof of the validity of sampling must be placed largely 
upon the repeated occurrence of consistent variations. 
2. Dominant year classes are normally present. 
