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;reen River a 10% angler take has been docu- nented for some years (USFWS, unpub. data). :his situation needs more evaluation; how- ver, loss of large, reproductive fish, particu- ll'ly females, may be significant. More and bet- .er angler contact and education and a more 19orous creel program could be beneficial. \.eSearch, Monitoring, and Data v.lanagement :he CRFP (\lv. H. Miller et at. 1982c; Shields 982; Wydoski and Hamill, this volume, nap. 8) is a cooperative USFWS project involv- ng the USBR, the USNPS, the USBLM, the states )f Colorado and Utah, and others. The project vas designed for rapid incorporation of infor- nation into ESA activities and recovery pro- :::rams. These goals were further supported by Jevelopment of the RIP in 1987, and annual -eviews are carried out in which needed mdies and information are given priorities md funds are allocated. The USFWS, under the UP, is computerizing an extensive data base. --" addition, joint annual research meetings lave been conducted by agencies and coopera- :ors each year since the early 1980s to aid in :educing isolationism (Wydoski and Hamill, :his volume, chap. 8). Monitoring is required as a follow-up to re- .zarch to maintain surveillance on the system nd to further refine management protocols. ~ong-term monitoring may also be geared to esting hypotheses, thus providing a dynamic :nput and fine-tuning management. Monitor- ng of Colorado squawfish involves, at a .:mnimum, periodic electro fishing surveys for --<<:lults as well as annual sampling of larval :Jroduction related to habitat conditions. Research, monitoring, and concomitant de- /elopment and refinement of management op- ::Ions are essential if recovery is to succeed. -;owever, these activities are just as valuable :or other freshwater species and other rivers. The Colorado Squawfish 399 The systematic damming of rivers of the world has reduced other fauna, particularly large endemic forms with complex life cycles like the Colorado squawfish. Included are other North American species like paddlefish (Po/yodon spathula) and sturgeons (Acipen- seridae), and Eurasian fishes like sturgeons and the cyprinids zheltosek (Elopichthys bam- busa), pikeasp (Aspiolucius esocinus), and others (Pavlov et ale 1985). Thes~ large river- ine fishes are rapidly disappearing, and the predicted extinction of many of the world's large migratory fishes (G. Howes, British Museum [Natural History], pers. comm.) may soon become a reality. Knowledge gained for Colorado squawfish will be useful in un- derstanding life cycles and habitat require- ments of these animals as well. The knowl- edge must be shared with others, however, which requires a commitment from agencies and individuals to publish their data and studies in widely circulated periodicals. Conclusions I j I I., !: I ! Loss of the Colorado squawfish, top carnivore of the pristine Colorado River ichthyofauna, would signal a final collapse of the most en- demic riverine fish community in North Amer- ica (R. R. Miller 1959), and perhaps foretell the doom of many of the large migratory fishes of the world as well. If the lower Colo- rado River ecosystem is indeed a model that predicts the outcome of water-resource devel- opment and the introduction of non-native competitors and predators in the upper basin (Molles 1980), the future is grim. The loss of species was not a national concern until re- cently, as indicated by passage of the ESA fewer than twenty years ago and the formation of active, concerned groups like the Desert Fishes Council. Recovery of the big-river fishes of the Colorado system is now a major issue in the battle against extinction. Although recovery li; !Ill Hlltl i 'iil :! I if I j: ::1 r '''J ! .11