644 
BULLETIN OF THE BUREAU OF FISFIERIES 
late fall. The eggs are deposited in the gravel beds of the streams to incubate during 
the winter months. They hatch out in the following spring and early summer. 
The young of some of the species remain in fresh water for a few years but they all 
eventually migrate to the sea where they mature. Since no definite knowledge has 
yet been obtained as to the location of most species of these salmon during their 
sojourn in the sea, their spawning migration is of primary importance to the fishing 
industry for it is only at this time that they are captured in large numbers. 
The responsibility of protecting this natural resource of Alaska from overexploita- 
tion, so that it may be preserved for future generations, is vested in the Secretary of 
Commerce who is advised by the United States Bureau of Fisheries. Since the 
demands of the industry for salmon are usually greater than the supply, the Bureau 
has found it necessary to regulate the fishery. This regulation aims to provide for 
an adequate escapement of the adult salmon to the streams so that they may reproduce 
and maintain their bounteous numbers. 
In the life-history studies of the Pacific salmon it was found that they have a 
high degree of homing instinct; i. e., the majority of the adults return to spawn in 
the streams of their origin. A discussion of the results of these studies may be found 
in the following references: Gilbert (1913), Snyder (1921 to 1924), Rich and Holmes 
(1928), Foerster (1929), Pritchard (1933 and 1934), and Davidson (1934). Owing 
to this peculiar characteristic of the salmon the population in each stream is self per- 
petuating and if once destroyed it will not be readily restocked through the straying 
of salmon native to other streams. Hence, in order to insure the maintenance of the 
salmon populations in the streams, it was necessary for the Bureau to provide for the 
protection of the spawning fish each season. In general it imposes definite limitations 
on the length of time fishing may be carried on in each locality, and prohibits fishing 
in and near the mouths of the streams and in the small bays that form resting areas 
for the migrating salmon. 1 2 
CHANNELS OF MIGRATION 
Figure 1 shows six main channels through which salmon may enter the inside 
waters among the islands on their way to the streams. These are, namely: Icy 
Strait-Lynn Canal, Chatham Strait-Frederick Sound-Stephens Passage, Sumner 
Strait, Cordova Bay, Clarence Strait-Ernest Sound, and Revillagigedo Channel- 
Behm Canal. Most salmon spawning in interior localities migrate through one or 
more of these channels to reach their destinations. In considering the conservation 
of the salmon populations in each locality the Bureau realized that some provision 
had to be made for the protection of these populations during their migration through 
the channels as well as in the streams. Hence, in order to expedite the patrol and 
regulation of the commercial fishery, the first and most logical step was to set apart 
the various spawning localities into fishing districts according to the main channels 
of entry through which their populations migrated from the sea. Before this could 
be accomplished satisfactorily, however, it was necessary to make a study of the 
migratory routes and destinations of the salmon populations passing through each 
main channel. 
1 For detailed information concerning the regulation of the salmon industry in Alaska see Laws and Regulations for the Pro- 
tection of the Fisheries of Alaska. Department Circular 251. Department of Commerce, Bureau of Fisheries, Washington, D. C. 
