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. DRAFT STUDY ARFA . This investigation was conducted within the same study area as described for the 87-88 winter in the final report. ME'mODOLOGY . This investigation was conducted using the same time schedules, methodologies and equipment as described in the Methodology section of the final report. HSI curves were not developed for northern pike due to insufficient data. . RESULTS . SUnlDary of Radiotagged Fish A total of 8 adult norther pike were caught by electrofishing and implanted with radiotransmi tters during the first phase of the 1987-88 investigation (Table 1). Six of the eight fish, when contacted, appeared alive and behavied normally. One pike, (GR-6110), was not contacted after release until the final tracking trip in late March. At that time, a signal was received at RMI 293.8, 21.2 mile below it's release point. The signal was triangulated to a point near midchannel in a shallow, moderately fast run. The fishes location was suspect, so extensive attempts were made to force the fish to move and then to retrieve the transmitter or carcass, with no success. It is suspected that the fish was dead or the transmitter was expelled. . . The other pike, (GR-6321) was found dead on February 21, floating near the surface of the water just beneath an overhanging ice shelf. Prior to that time, the fish had been contacted on the three previous tracking trips in the same general river reach and seemed to be behaving normally. The carcass was in good condition with the exception of an abrasion on the right side near the dorsal surface and was taken to the lab at BIOjWEST for necropsy. . Results of the necropsy showed that the fish was a ripe female. Tissues surrounding the radio transmitter were healthy and the incision was completely healed, although the sutures were still in place. Large amounts of adipose tissue were present around the ovaries and pyloric caeca. stomach contents included a bluehead sucker, measuring approximately 200 rom TL, that had been recently ingested. A large contusion was found on the right side of the fish near the dorsal surface, immediately below the skin abrasion. Three ribs were also broken near their insertion with the vertebrae in the area of the bruise. The air bladder was also burst, but it was inconclusive whether this contributed to or was subsequent to the death of the fish. No other injuries or abnormalities were apparent. It is speculated that the fish was using an overhanging ice shelf for cover and was crushed to death when the ice cleaved and collapsed into the river. . . 48 .