National Geographic : 1907 Jun
OUR FISH IMMIGRANTS BY HUGH M. SMITH DEPUTY U. S . COMMISSIONER OF FISHERIES NE of the most important, exten sive, and interesting lines of utilitarian work conducted by the federal government is the transplant ing of native aquatic animals into waters in which they are not indigenous, and the introduction of fishes of foreign countries into the United States. Most people are familiar with the economically important results of acclimatizing foreign species or varieties of mammals and birds in our country, and every one can recall some of the many valuable vegetables, fruits, and other plant products that are immigrants; but comparatively few people are aware of the systematic and varied measures that have been taken by the government for increasing and enriching the supply of food and game fishes of every section of the country, and still fewer realize the ex tent to which the commercial fisherman, the sportsman, the youthful angler, the farmer, and the public in general are in debted to the National Bureau of Fish eries and the state fish commissions for providing many kinds of useful creatures that did not originally inhabit given waters. oBJECTS OF ACCLIMATIZATION When we contemplate our wonderful aquatic resources-unsurpassed asa whole for variety, abundance, and excel lence-the question naturally arises as to the necessity for planting non-indigenous species in any of our waters. The occa sion for such efforts comes from a num ber of conditions which have been duly considered by the authorities; among these are: (i) The depletion of the indigenous fishes of given waters and the inability to secure the reestablishment of those species, either by restrictive measures or by arti ficial propagation, owing to changed or changing physical or biological condi tions. (2) The possibility of enriching the fish fauna of a given water by introducing more useful species than already exist therein or by affording a greater variety of fishes for food and sport. (3) The existence of physical or. other conditions more inimical or unfavorable to the native fishes than to other fishes that might be introduced. (4) The possibility of relieving the drain on native species by providing new objects for the pursuit of the angler and the commercial fisherman. (5) The desirability of .reducing the abundance or securing the extermination of noxious fishes and other water animals by planting fishes which will prey thereon. Features of aquatic acclimatization which may be noted especially are the in terchange of products between the east ern and western parts of the country, the introduction of eastern fishes into new waters of the east, and the importation into the United States of fishes from foreign countries. This work has af fected not only the lake and pond fishes, but also the migratory river fishes of both seaboards and some strictly salt-water forms; and since, for practical purposes, the term "fish" has generally been con strued as meaning every kind of animal taken from the water for profit or pleas ure, the operations have involved many creatures that the biologist would not class as fish.