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Is Our Native Underwater Life Worth Saving? By Robert R. Miller' D RING THE PAST TWENTY-FIVE years, there has been a steadily increasing application of chemicals to our lakes and rivers for the removal or depression of "undesirable" fishes. Now every State in the United States and all of the provinces of Canada em- ploy this method as a fishery-manage- ment tool. Between 1952 and 1962, for example, the U. S. Fish and Wildlife Service, through its Dingell-Johnson program of federal aid to the States for fish restoration, supported the poison- ing of some 225,000 acres of lakes and 2,500 miles of streams. Yet this is but a fraction of the waters so treated because each State carries out its own eradication pro- gram. In concentrations as low as 0.5 part per million of 5 percent rote- none, this chemical is toxic enough to kill most fishes and many other aquatic organisms with which it comes into contact (Burdick, Dean, and Har- ris, 1955). Death results, to put it simply, from suffocation. Some fishes (e.g., the gizzard shad) are so sensitive that concentrations of 0.10 to 0.15 ppm are fatal. Much higher concentrations are commonly used. Yet little is known of the effects of rotenone-containing products on aquatic insects, float- ing animal life (zooplankton), and bottom-dwelling invertebrates that are so important to the welfare of higher aquatic animals. A general disre-ard has been shown for the aquatic com- munity as a whole. This includes not only a variety of fishes. not all of which can be "undesirable," but also entire, complex food chains of organisms, in- cluding many that are kilted outright and all of which must be adversely affected. And, until very recently, there has not even been any voiced opposi- tion to fish-management programs that involve the wholesale poisoning of large numbers of native aquatic ani- mals. Man so often exercises the kind of foresight and motivation that seeks the biggest immediate gain and dis- play, heedless of the long-term results. Intentional poisoning S of waters by the States as well as by the federal government is said, by these groups, to be necessary in order that "trash fish" populations be removed or de. pressed, with consequent "rehabilit . tion" of the waters im oh ed. Unfor- tunately, the term "trash fish" includes native as well as introduced species. Moreover, native fishes often suffer far more heavily than introduced kinds; the carp, for example, is quite resistant to fish toxicants. Furthermore, such ' Support for field work on tike Crren River, given the author by the U. S. National Sci- ence Foundation, is gratefully acknowledged. 'Some fish managers object to the term poison, claiming that since the organisms are killed by suffocation they are not poisoned. This is nonsense. Any substance that when taker. into the system acts in a noxious man- ner by means not mechanical, to as to cause death or serious injury to health is a poison, by dictionary definition. Aloreover, rotenone is given as a dictionary a-xampie of a poison. catch-terms as "rehabilitation" are often exploited for propaganda pur- poses to convince the public that wide. spread elimination of the fauna of whole river systems is a good thing (Anonymous, 1962; Stone, 1962). Pro- fessional molders of public opinion have thus so slanted their publicity on these programs as to mislead the pub- lic. It is to be emphasized that destruc- tion of native forms has been under- taken by conservation departments and fostered by an agency (the U. S. Fish and Wildlife Service) that is charged with conservation of our natural re- sources. Short-term, economic gains resulting from the temporary increase in numbers of some favored gamefish at times have been given precedence over biological losses by those respon- sible for the management of our waters. I do not deny that fish toxins have an application in fishery management that may be both economically and biologically sound, and that wise use of such chemicals is desirable. Ex- amples of such use involve application to particular, limited bodies of water -such as wholly enclosed lakes, arti- ficial ponds, and man-made reservoirs -for the relief of localized specific problems. Excessive stunting, such as not infrequently occurs in the yellow perch, and over-population by an exotic species that leads to interference with reservoir or pond management, are local problems that may properly be relieved by this approach. The tool has also been used beneficially to gain NATIONAL PARKS ItfAGAZ1NF.