244 
BULLETIN OP THE BUREAU OF FISHERIES 
all restrictions on the amount of fishing apparatus used by each boat after August 10. 
The same regulations were continued in 1926 except that the closed season was short- 
ened 9 }/2 days, minor prohibitions in the use of 83/2-inch mesh nets within 2 miles of the 
mouths of streams were added, and the weekly closed period, was extended to 60 hours 
through July 10. In 1927 the weekly closed period was changed to 48 hours from May 
20 to July 10, boats were limited to the use of 250 fathoms of net except that from May 
20 to May 31 an additional 100 fathoms of 8 3/2-inch mesh gill net could be used. 
During this period of ad j ustment the catch of salmon fluctuated considerably from 
year to year, possibly due to the continually changing regulations and irrespective of 
the size of the runs. When the drastic regulations of 1925 became effective, the catch 
of red salmon dropped to the lowest level it had reached in the entire history of the 
Copper River fishery, only 160,721 being taken, and the catch in 1926, under a slight 
relaxation of the regulations, was only 211,311 reds, next to the lowest ever made. 
The catch had not fallen below half a million during the entire period from 1914 to 1924, 
inclusive. 
In 1918 the catch was nearly a million and a half reds, 20,000 kings, 75,000 cohos, 
and a few hundred pinks and chums. This catch was produced by an aggregate of 
37,500 fathoms of gill nets, 36 dip nets, and 2 traps. In 1920 the catches of all other 
species than reds was about the same as in 1918; but the catch of reds was much smaller, 
only a little over 850,000 in spite of the use of considerably more gear — 57,400 fathoms 
of gill nets, 183 dip nets, and 3 traps. The regulations for these two years favored 
the season of 1918 as the longer closed season in 1920 and the closure of certain areas 
in the up-river fishing grounds naturally reduced the catch in that year, but it would 
seem that an increase of 52 per cent in the fishing effort would more than counter- 
balance the additional restrictions then applied although it is possible that the catch 
per unit of gear may have been materially decreased by the competition between 
units. (See Pt. I, p. 77.) A comparison of the catches in 1919 and 1920 under identi- 
cal regulations and with practically the same amount of gear shows a difference of 36 
per cent in favor of 1919. It is probable, therefore, that this smaller catch in 1920 was 
due to biological causes and reflected a smaller run of salmon in 1920. 
Figure 10 shows in graphic form the catch of king and red salmon in the Copper 
River district for 39 years. 
In respect to red salmon, the graph shows that the first noteworthy peak in 
production was reached in 1902 and 1903; this seems to be due entirely to the number 
of canneries operating rather than to the quantity of fish available, as with each 
increase or decrease in the number of operators the catch rose or fell correspondingly. 
After 1903 the catch immediately dropped to a much lower level for the simple 
reason that but one company was then operating. For the same reason it remained 
low during the next 10 years, the catch limit being fixed by the packing capacity 
of the cannery and not by the size of the run. In later years, with the introduction 
of more canneries, the size of the catch undoubtedly bore a direct relation to the size 
of the runs; and this continued until regulations changed the situation, affected 
operations, and reduced catches so as to leave no basis for determination of size of 
runs by measurement of catch in a single season. The number of kings and cohos 
taken in 1927 was nearly double that of any other year; chums and pinks are prac- 
tically unknown in the district. 
No definite evidence of serious depletion, therefore, can be seen in this district 
in spite of the greatly reduced catches of red salmon since 1924, since the catches of 
recent years have been made under totally different conditions. If the small catches 
