PROGRESS IN BIOLOGICAL INQUIRIES, 1926 637 
STUDY OF THE EFFECT OF SEA FISHING 
It is generally believed that trolling and purse seining for salmon in the ocean, as at 
present conducted, is destructive, especially of immature fish. Various details neces- 
sary for intelligent control of this fishery should be worked out in each locality. Irom 
the tagging of troll-caught fish we will ultimately learn the interrelations of the fish 
caught at different places along the coast; and we should know, in addition, certain 
details for each fishing locality, such as the percentage of immature fish taken at dif- 
ferent times during the year, the loss due to fish hooked but not landed, etc. 
It is recognized that many of the fundamental facts of the life history of 
the salmon are fairly well known; in this respect we are fortunate in having 
a good foundation on which to build. We have good methods for tagging, 
marking the young fish, and for making scale readings, and these may be 
applied to the working out of many of the details that will be required. Many 
minor details can be and are being studied in connection with some of the 
larger problems mentioned, but it has not been thought necessary or desirable to 
bring forward at this time too many of the details. 
Not all of the items in this program can be undertaken immediately, but it 
is hoped that ultimately the program, in its entirety, may be accomplished. We 
wish to emphasize, however, the importance of selecting the more important 
practical problems for first attention. These practical problems may not be the 
most interesting or the most fundamental, but may be urgently required as a 
basis for immediate administrative action, without which serious and perhaps 
irreparable damage to the salmon runs may results. 
We have been conducting special studies on the salmon stock in Bristol Bay, 
Alaska. Bristol Bay is the greatest red-salmon producing area of its size in 
the world. There are a number of large streams, each heading in large lakes, 
one (Iliamna) being nearly 100 miles long. There are other lakes above 
Tliamna, connected with it by rivers. Spawning of the red salmon almost 
invariably takes place in these lakes, where the young remain for a year or 
two. At one time there were 30 or 40 canneries in this region. The production 
is upwards of 1,000,000 cases a year. The question was whether the fish 
taken in this fishery were of local origin or from somewhere else. Of the fish 
we took, we found that a considerable percentage belonged in Bristol Bay. That 
naturally threw a light upon the conservation problem there. 
That is an outline of the general program. I, as you know, have been out 
of the work for some time and have only very recently gotten back into it, so 
I shall ask Doctor Gilbert to tell you more about the work that actually has 
been accomplished on the west ceast recently and for which he mainly has been 
responsible. Doctor Gilbert, as you know, is the leader, I might almost say 
the originator, of fisheries research in this country, and I presume there are a 
great many of us here to-day who would not be here if it were not for the 
work Doctor Gilbert has done. 
SALMON 
By Dr. C. H. GitBert 
I shall speak briefly on the work we are attempting to accomplish in the 
Kodiak region, to which Doctor Rich has referred—a region that lies south of 
the Alaskan Peninsula and is the site of an important salmon fishery. 
Among the multifarious duties that devolve on the Bureau of Fisheries 
there are no others, I venture to say, that are so exacting and entail such heavy 
responsibilities as the administration of the salmon fisheries of Alaska. In 
1924, recognizing the precarious condition of these fisheries, Congress passed 
a bill that granted extraordinary powers to the Secretary of Commerce to enable 
him to control the fisheries of Alaska and prevent their further depletion. The 
powers thus granted made it possible to limit the fishing in any district to what- 
ever extent seemed necessary, or to close it to fishing entirely for a term of 
years, if serious depletion already had taken place. The kind and extent of 
fishing could be prescribed in any area, and, in general, such regulations im- 
posed as would prevent the disastrous effects of overfishing or would restore 
the yield in such districts as had suffered already. The entire responsibility 
for maintaining the yield of this most important salmon fishery was thus placed 
squarely on the Secretary of Commerce, and through him on the Bureau of 
Fisheries. 
No one except those who have been directly concerned with the administra- 
tion of these fisheries can appreciate the complexity of the problems and the 
inherent difficulties of the task. There are five different species of salmon of 
