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Reviews In mecting in Hot Springs, Arkansas. That meeting was well attended by those who dcCcnded introduction of the grass carp (CtcllopllllrYIlf!,odol1 idc/hl) and opposed any national or profes- sional restraints to the freedom of act ion of the individual states. The Exotic Fishes COlllmittee, of which the present authors were members, was surprised and pleased that the policy was approved at that time and place. Administrative arrogance had been displayed in statements concerning rights of an individual state to introduce organisms which, if successfully established, would clearly range beyond that state's boundaries, and to do this without consulting with neighboring states or adjacent countries. This arrogance was no doubt a factor in the passage of the position statement. Our hopes that this good start would signal genuine appre- ciation of the scope of the problem and that the procedure would be quickly adopted on a wide scale were naive. Kohler and Courtenay" noted that the position statement received little recognition and was rarely followed. Nevertheless, one positive result was that the Exotic Fish Committee evolved. in a series of steps, into the Introduced Fishes Section of the American Fisheries Soc iety. Not much happened with regard to procedure on introduc- tions until 1986, when Kohler and Courtenay, 7 reporting for the Environmental Concerns Committee of the American Fish- eries Society, presented an altered policy statement that was 8pproved by the Executive Committee of the society in Sep- tember 1986. The changes arc easily noted, for Kohler and Counen;ty7 inuicated all deletions in the earlier position state- ment by lined-through text and the few additions by underlined \vords. The new policy deleted all references to the need for facilities and research on fish diseases, as well as a call for kgislation which would regulate certain aspects of construction of fish farms, construction that would greatly reduce the chances for 3ccidentai release of stocks. Dr. Stanislas F. Snieszko had ;,;-gucd ahly for inclusion of support for studies on fish diseases but, with his death (in 1984), inlerest in that area quickly faded, at least as far as inclusion of it in a policy statement. The one important change in the procedure was the deletion of the statement, "This agency or organization should not have the authority to approve its own results or to effect the rclease of slocks, but should submit its report anel recommendations for evaluation." This deletion, in our view, is fatal to the policy because agencies bear the responsibility for many introductions of great environmental concern.2.X-IO The deletion was made because the committee believed, or was advised, that the over- aU policy "','oulel not be approved without it. It is important to remember that the initial position statement, with the restraint included, \vas approved under politically adverse circum- Slances. We regard the deletion as ill-advised and unnecessary. \Ve use the term introductions to mean release of fishes into waters in which they are not n;ltive. in contrast to stocking of a species, native or not, where it mayor may not be established but requires periodic surrlementation from hatchery stocks. It 1~,., :,):~} is not our intent to recount a history of fish introductions into North American waters, provided elsewhere hy numerous au- thors, but to provide a few case histories which examine some past (before profcssion;d pol icy or posit ion statements were approved) and current or inlpending introductions. Clearly, there is an increased use of introductions in fisheries manage- ment. We are convinced that many introductions are mistakes and indicate mismanagement or no management of. fishery resources. Some may regard several of our examples 10 be negatively biased, but knowledgeable fishery biologists and managers will see parallels in their jurisdictions and experiences. II. THE SALTON SEA EXPERIENCE: A LESSON IN SUCCESS One of the besl examples of serendipitous fishery managc- ment using introductions involves the Salton Sea, a saline body of water lying below sea level in the Salton Sink of southern California, north of the Colorado River delta. A single juris- diction, the state of California. was involved. In the Tertiary Period, the Salton Sink was the northern end of the Gulf of California; it later became landlocked due to delta building, and dried. It has been periodically wet and dry in subsequent geologic periods. During Pleistocene pluvial periods, it re- ceived water from the Colorado River, forming Lake Cahuilla,_ which drained south into the Gulf. Hubhs and Miller,1I citing Mendcnhall'~ and Rogers, I.' slaled that Lakc Cahuilla was full to the ancicnt be;lclllinc from 1000 10 perhaps only :mo years ago. Sykes'! estimated that the Salton Sink has been periodi- cally. but only partly, inundated five times during the last century, resulting from flood waters of the Colorado River cutling lhrough lhe upper delta. From 1905 to 1907, during cOllstruction of an agricultural canal along a past nood channel (Alamo River) into Imperial Valley from the lower Colorado River ncar Yuma, Arizona, extreme flooding caused the river to burst through its banks and the nearly finished canal to flood thc Salton Sink. Fresh- water organisms, including fishes, were carried from the Col- orado River into the sink with the flooding.""'~ Agricultural canals, most built since the 1905 to 1907 nood- ing, have kept the Salton Sea from drying via inflows of Col- orado River water and back flow of irrigation and domestic wastewaters, anel actually increasing the depth through the 1950s.'~ Leaching of salts and evaporalive concentration, how- ever, quickly increased the salinity of the sea, eliminating the freshwater fauna. In 1907, the salinity was 3.6%0; in 1956, it was nearly 33%0; ". and in the early 1980s it approached 37%n. 17 Although the Salton Sea is saline, its chcmical composition is not that of seawater. It contains less magnesium, potassium, and chloride ions; more sulfate, calcium, bicarbonate and car- bonate ions; but about the sante sodium ion content. It. After 194X, Colorado River innow exceeded evaporation and salinity decreased somewhat; in recent years, however, salinity has Volume I, Issue 1