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Reviews In North Dakota, with the se,:sonal and periodic changes in water levels there. Third, rainbow smelt will enter the Colorado Ri~r below Powell Dag1, where they will doubtless provide forage for trout in the Lees Ferry/Marble Canyon area. Furthermore, their passage through the Grand Canyon into Lake Mead is likely, as is subsequent dispersal into other reservoir~ downstream. While rainbow smelt are not expected to reproduce in the Grand Canyon portion of the Colorado River, they could ad- versely impact the few remaining native fishes there. Further- more, Arizona. California, and Nevada will probably inherit Utah's management problems in their reservoirs, and the en- demic fish fauna dowstream will be impacted. The likelihood of rainbow smelt becoming established in one or more reser- voirs downstream is great. Moreover, should rainbow smelt spread as far south as lower Lake Havasu, they wi II have access to the Central Arizona Project (CAP) Canal with dispersal into the Salt and Gila river reservoirs and streams toward the Mo- gollon Rim virtually assured. We ask if Utah is prepared to pay for damages to fish resources of adjoining states should this introduction prove detrimental? Notably absent from Utah's proposal to introduce rainbow smdt into Lake Powell are data as to factors other than pre- dation that might have caused declines of resident introduced fishes. If Lake Powell and Flaming Gorge were nutrient traps that affected Lake Mead, is it illogical tliat Flaming Gorge is a nutrient trap for Powell? Are nutrient supplies to Lake Powell sufficient to support plankton productioll' for threadfin shad? If not, it is pointless to even consider the introduction of yet another plankton-feeding forage fish to Lake Powell. Much to the credit of the UDWR. a proposal for introduction of rainbow smelt was developed and disiributed beyond that agency for outside review by the Colorado River Wildlife L~ouncil (See below). *' Me;lnwhile, the U.S. rish and Wildlife Service has proposed reintroduction of the Colorado squawfish (P/yc/lOchci/l/s /1/- cil/s) into a prime portion of its past range in the lower Colorado basin, between Parker and Imperial dams.'7 We would view this as a positive management procedure had the introduced population not been declared "experimental, non-essential" and, in this case, open to immediate sport fishing. Experimental reintroductions of endangered fishes into their historical ranges Ivcrc originally designed to categorize the reintroduced species ~!s threatened, tbereby allowing greater freedom in monitoring, i~)clud!i1g taking of specimens for research purposes. While ibis (:pproach may circumvent objections to reintroductions by state fishery agencies and private special interests, it can result in reestablishment of endangered species, a positive aspect. Two categories, however, for experimental reintroductions - essential and nonessential - appeared in lhe final rule, the Lacr circumventing intCl'<lgency consullations required under t:1C Enclangcrel! Species Act. Nonessential cl;lssifieation can ;~no'." st;,,~cs to (nc~\ ;~ o'~\lr', Lshery on a reintroduced enc!;II1- gered species before it has been reestablished and build pop- ulations, a management possibility that we view as patently amoral. In this instance, we ask if this is an attempt to rees- tablish a fish and recover an endangered species or to create a sport fishery, possibly on a put-and-[ake basis, [0 be supplied by a federal facility created to preserve and reintroduce en- dangered fishes? It is, however, a policy of the U.S. Fish and Wildlife Service to publish proposals for reintroductions of endangered species and expose such proposals to outside re- view, with invitation for commentary by interested parties which, in our view. is a positive approach to potentially wise resource management. V. THE WALLEYE AND THE ZANDER Our native sauger (S/izo.l'/cdio/l cOl/i/(Ic'I/.I'c). walleye (S. I'i/- rC1/1Il l'i/rcl/lI/), and the extinct blue pike (5. l'itrclIlI/ g/Ol/CIIII/), have two relatives in eastern Europe, the zander (5. /uciop- crCO) , frequently called European pike-perch, and the Volga pike-perch (S. I'O/gcl/sis), also known as the Volga zandcr. North Dakota is proposing to introduec zander into Lakc Sak- akawea, an extensive reservoir on the Missouri River above Garrison Dam. Lake Sakakawea has been reputed to have some of the finest walleye fishing in North America; sauger also occupy the reservoir. The forage base for walleye in the res- ervoir is largely rainbow smelt, introduced in 1971.'" The walleye population has declined in recent years. the decline attributed to water level fluctuations through diversion, ex- posing vegetation where walleye spawn to drying, and to fluc- tuating water temperatures during spawning and recruitment periods..'" l~is also (m'i8blc, however thaI rainhow smelt may h~ contributed to decline of wallcye throu~h prcdation on youUJi.. C;:-peeiallv with fluctuating water leyels, although this factor scems not to have heen examincd or considered. In lieu of stocking or limiting waler diversions in seasons when walleyc arc not spawning, North Dakota seel1ls bent on introducing zander. Clai ms arc made that reproduction of zander is less alTccled hy water level fluctuations allll, thcrcrore, successful spawning and recruitl1lent should occur. We fail to undcrs[and that argument, because zander usually spawn on sand and gravel bottoms in shallows and on roots of large aquatic plants;(,(I surely those habitats arc also affected by water diversions C<IUS- ing reservoir level fluctuations. Zander. however, have a longcr spawning period than walleye, build redds, and guard their young against predators, thus assuring higher survival and re- cruitment rates than walleye.i" These factors, while favoring zandcr, can also work against other fishes in Lake Sakakawea and downstream. perhaps in ways similar to displacement or replaccment of fishcs in the lowcr Colorado hasin by introduced [ilapias." /\-brsh;dl'd suggcstcd zander as suitahle for intro- '\. duct ion hut in situations considered irrevcrsibly adverse (hat arc unfit for comparable native fishes.