10 -A REVIEW OF THE HISTORY AND RESULTS OF THE ATTEMPTS TO 
ACCLIMATIZE FISH AND OTHER WATER ANIMALS 
IN THE PACIFIC STATES. 
By HUGH M. SMITH, M. D. 
PREFATORY REMARKS. 
Few subjects connected with the utilization of our natural resources present 
greater interest than the possibilities for the successful transfer of useful animals from 
one section of the country to another and their acclimatization in new regions. The 
benefits that may accrue to a community or section through the introduction of new 
resources are various, and there are few parts of the country in which valuable 
non-indigenous animals are not now found. 
In the case of water animals, the benefits of successful acclimatization are doubt- 
less proportionally greater than with any other class, owing to the little attention they 
require after introduction, their extraordinary fertility as compared with land animals, 
and the slight labor and expense incident to their utilization. At the same time, it 
is apparent that the difficulties in the Avay of introduction of fish, mollusks, etc., are 
greater than with other animals; the drawbacks in the mere transportation are often 
very serious, especially when long journeys are to be made; while the uncertainties 
attending' the deposition of the animals, the determination of the general results, and 
the gauging of the economic effects are much greater. 
Among other influences militating against the successful introduction of fishes 
and other aquatic animals into new areas, in addition to those incident to their trans- 
portation, are the following: (1) Unsuitable water temperature; (2) unsuitable food; 
(3) unfavorable topographical condition of the bottom; (4) absence of suitable rivers 
for anadromous fish ; (5) enemies and fatalities acting on a relatively small number 
of individuals. 
The results attending the experimental introduction of aquatic food animals into 
the waters of the Pacific States must be regarded among the foremost achievements in 
fish-culture. The striking illustrations here presented of the influence of man over the 
supply of free swimming anadromous fishes, to say nothing of his ability to affect the 
abundance of non -migratory species, are of great economic and scientific interest. 
Aside from the direct economic results which have followed the introduction of 
east-coast fishes into the waters of the Pacific States, a very important basis has been 
furnished for judging of the general effects of artificial methods in regions where the 
object of fish-cultural operations has been to maintain and increase the abundance of 
native species. Attention was first drawn to this phase of the subject in an article 
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