18 REPORT OF THE COMMISSIONER OF FISHERIES. 



chinook salmon in the Columbia and Sacramento Rivers. Further 

 .consideration has been fjiven to the capture of immature salmon in 

 the open ocean, a commercial practice which threatens the future 

 of the salmon industry, and a conclusive report may be expected 

 shortly. Investigators have made significant studies of salmon in 

 Alaska, the results of which will serve as a guide both in fish-cul- 

 tural practices and in the administration of the salmon fishery in 

 Alaskan waters. 



There have been conducted anatomical studies and experiments 

 with members of the salmon family which have brought to light con- 

 ditions that bear directly upon the propriety and effect of certain 

 fish-cultural practices, and that with further study and experiments 

 at hatcheries are expected to lead to improvements in the manipu- 

 lation of brood fish, and thereby promote efficiency and economy in 

 the o]:)eration of trout stations. 



The Bureau is also endeavoring by a series of studies, unavoidably 

 technical in nature, to clear up the confusion existing as regards the 

 relationships of the several members of the salmon family, a con- 

 fusion which is not of theoretical interest alone, but which impedes 

 the efficiency of practical work in the distribution of fishes, which 

 should be based upon definite knowledge of the species propagated 

 and distributed and of the natural range of these and related species. 

 It is sometimes difficult to determine the results of the introduction 

 of species of trout in new waters (as, for instance, the many disputes 

 regarding rainbow and steelhead trouts) because definite criteria are 

 wanting to identify the species propagated on different occasions, or 

 the species found to have become established in the planted waters. 



STUDIES OF OTHER FISHES. 



A similar sort of obscurity with reference to the species of white- 

 fishes and ciscoes, or so-called lake herrings, of the Great Lakes has 

 been attacked, and there was brought to completion during the j^ear 

 the report of a thorough study of the whitefishes and related species 

 in Lake Huron. The investigation will be extended to Lake Michi- 

 gan in the course of the present year. 



The investigations of smelts which have been pursued during a 

 period of years are nearing completion, and the results will afford 

 long-desired information regarding fishes that are esteemed for their 

 value as human food and that are of even greater value as food of 

 the larger food and game fishes. 



The investigation of the paddlefish has been continued, but the 

 species still baffles the most careful inquiry into its habits of breed- 

 ing. The life histories of marine fishes are receiving persistent atten- 

 tion, and it is expected that substantial contributions in this field 

 may be made at an early time. 



In response to many inquiries regarding the possibilities for a 

 sardine-packing industry on the northwest coast, the Bureau con- 

 ducted a further inquiry into the occurrence of pilchards, or sardines, 

 off the coasts of Washington and Oregon. It was ascertained that 

 sardines occur in these waters irregularW, though abundantly at 

 times, but, in view of the uncertainty of the runs, the difficulties of 

 the fishery, and the general situation in the canning industry, the 

 establishment of sardine canneries in the northwestern States at the 

 present time is not recommended. 



