2.-A PRELIMINARY REPORT UPON SALMON INVESTIGATIONS IN IDAHO 
IN 1S94. 
By BARTON W. EVERMANN, Pit. D., 
Ichthyologist of the United States Fish Commission. 
In this report are presented the results of certain investigations, carried on under 
instructions of the Commissioner of Fish and Fisheries, concerning the abundance, 
distribution, and spawning habits of the species of salmon which have spawning- 
grounds in the waters of the State of Idaho. 
The alarming decrease in the salmon catch of the Colombia Fiver within recent 
years, the importance of preventing the continuance of this decrease, and the desire 
and hope that the salmon industry may be rebuilt to its former importance, render 
imperative a most careful study of the natural history of the salmon and a more accu- 
rate knowledge of the location of their spawning-beds, their time of spawning, and the 
temperature and other physical conditions under which their spawning takes place. 
These investigations were really begun in 1S93, when the present writer, assisted 
by Dr. Charles H. Gilbert and Dr. Oliver P. Jenkins, both of Stanford University, 
made an examination of the obstructions in Snake River and in the Pend d’Oreille 
River, the report of which has been published.* During the spring and summer of 
1891 they were continued on the Columbia and lower Snake River by Dr. Gilbert, 
whose report is now in preparation. 
I left Washington September 1, 1894, and, being joined at Terre Haute, Ind., by 
Dr. J. T. Scovell, proceeded to Shoshone Falls, Idaho, where the work was begun. 
Our attention was directed chiefly to three localities: (1) The streams and lakes at 
the headwaters of the Salmon River; (2) the streams and lakes at the headwaters 
of Payette River; (3) that portion of Snake River lying between the Great Shoshone 
Falls and Huntington, Oreg. 
In the following pages is given a somewhat detailed account of the physical 
features of the waters of each of these regions, and then follows what we have been 
able to learn regarding the three important species of Salmonidte which ascend to the 
waters of Idaho for spawning purposes. These species are: (1) The chinook salmon 
(Oncorhynchus tschawytscha ); (2) the blueback salmon or the redlish of Idaho ( Onco - 
rhynchus nerlca ); (3) the steelhead or salmon trout (tialmo gairdneri). 
Although less than five weeks’ time was given to this work, it is believed that 
new and very important facts were discovered regarding these three valuable food- 
fishes, and only the lateness of our arrival upon the spawning-grounds prevented our 
* Report of the Commissioner of Fish and Fisheries on Investigations in the Columbia River Basin 
in regard to the Salmon Fisheries; issued as Senate Mis. Doc. No. 200, Fifty -third Congress, second 
session, 1894. This report contains “A report upon investigations in the Columbia River Basin, with 
descriptions of four new species of fishes, by Charles H. Gilbert and Barton W. Evermann.” 
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