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.- initiated in 1985 by the Arizona Game and' Fish Jepartment and Dexter National Fish Hatchery (Hendrickson and Brooks 1987). It is too soon to determine the success of that endeavor, but it is doubtful if stocking alone will be sufficient to recover the squawfish there. Indeed, the complex life cycle of the Colorado squawfish, in which there are spatial separations of life stages, incorporation of an energetically-costly migratory behavior, and other components (Tyus 1986, 1990) suggests that stocking programs can only be successful if life history attributes are understood and considered. A small experiment station has been established near Vernal, Utah for razorback sucker recovery. Fertilized eggs are taken from the field and placed in incubators for development of brood stock and experimental work. Stocking of young razorback suckers thus produced have been initiated in the Green River. However, this is only done to augment a non- recruiting population (Lanigan and Tyus 1988, Severson et al. 1989), and in support of research studies. Non-native Species and Sportfishing Stocking of nonnative, warmwater species has been reduced in the upper Colorado River basin recent years, and under the RIP would not occur in watersheds occupied by listed fishes. The reverse of stocking non-natives, i.e., their elimination or removal, is worth considering, but this issue has not been meaningfully addressed as Jet. Introductions of fishes into habitats occupied by:native fishes may adversely effect native fishes, especially if habitats have been altered. Direct effects include: Elimination, reduced growth and survival, changes in community structure, and no effect (Moyle et al. 1986). However, such effects are difficult to assess because fish are usually introduced into habitats that are changing due to the effects of man. Thus, it is difficult to determine if habitat change, competition, or both, are responsible for declines that have been noted. This already complex issue is further confounded by past introductions into waters in which species interactions were not well understood, and were usually not subsequently studied. Thus, impacts of introduced fishes on native popul at ions are seldom understood. Because it 'i s difficult to assess such impacts, and the effects are usually inferred from major alterations of species composition. Competition between native and introduced forms is difficult to observe experimentally, and perhaps impossible to prove in natural riverine habitats. The introduction of. non-native fishes in the Colorado River begain in the late 1800s and it has been documented by many. Some data on the present status of various introduced fishes' is provided by Minckley (1982) and Tyus et al. (1982). Competition of these non-natives with Colorado squawfish has been proposed by various workers (Behnke and Bensen 1983; Holden and Wick 1982; Osmundson 1987). Predation of introduced fishes on razorback sucker eggs and fry has also been reported, and implicated as a factor in the lack of recruitment for this species (Marsh and Langhorst 1988, Marsh and Minckley 1989). Introduction of channel catfish, northern pike and other fishes into the Green River has had an unknown effect on native fish populations. However, the predaceous nature of these species makes them suspect (Tyus and Beard 1990, Tyus and Minckley 1988, Tyus and Nikirk 1990). Much has yet to be done in the laboratory and field to evaluate specific interactions. Research, Monitoring, and Data Management The development of management programs for Colorado River fishes will require well- organized and applied research to develop and test management-related hypotheses. Monitoring of management practices is also required as a follow-up ~n research findings to further r~fine management options. These programs all requlre an extensive database management system to organize, store, and make available collected information. Development of the RIP in 1987 included provisions for regular meetings of a technical review group, and annual review of past work in which needed studies and information are prioritized, and funds are allocated, as available, to obtain information. The Fish and Wildlife Service has been given the lead ~nder the RIP, to proceed with computerizing the extensive amounts of data collected by Federal, State and private agencies and individuals. In addition, an annual research meeting has been conducted by cooperators each year since the early 1980s to aid in increasing awareness, sharing informatin, and reducing isolationism. FUNDING Study of native Colorado River fishes is difficult and costly. Yet much habitat alteration has been caused by construction of federal reservoirs. These produce large revenues, and it seems only proper that some of these funds be used to aid in the recovery of the native fish fauna. Indeed, much of the funding for the upper basin recovery effort has been contributed by BR (about $6.5 million, or less than 0.05% of the total; R.D. Williams, personal communication). These funds are used to support research and management projects, but they have also made possible the retention of fisheries biologists in the BR and USFWS, whose function is to: conduct and manage research; cooperate with. and foster interests in, other workers in academic and private sectors; and to interpret and apply research results to biological conservation 11t ,....... t'. ii , ( I, :-. ~ It til : l ~ t , , ; :.I"'.J "',1 ,Ir 'I' i) ;.i..i..:I. ' !.~. , 1) \' j Ii' ; I~' j III'. I r~ ' (: 11 I I! 1.'1 : i.~ I , ..l 'ii'II II.il.......... II!: 1:, r' ! 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