THE UNEXPECTED APPEARANCE OF PINK SALMON 

 IN THE KVICHAK RIVER 



Clarence D. Becker 



In the fall of 1958 there was abundant spawn- 

 ing by pink salmon (Oncorhynchus gorbuscha ) in 

 the Kaskanak Flats area of the Kvichak River in 

 Bristol Bay, Alaska. The Kvichak River, which 

 is approximately 55 miles long, drains from Lake 

 Iliamna and flows into Kvichak-Naknek Bay. The 

 unexpected appearance of these fish occurred si- 

 multaneously with a tremendous, and also unex- 

 pected, run of pink salmon in the neighboring 

 Nushagak River. 



Spawning area 



Extensive spawning occurred in the sur- 

 veyed section of the Kaskanak Flats, a series of 

 shallow channels extending uprive r approximately 

 eight miles from the head of tidewater. Above 

 the flats, spawning took place largely in shallow 

 side branches of the main channel. The head of 

 the Kvichak River at Igiugig was the upper limit 

 of the spawning. 



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Occasional pink salmon were observed in 

 the upper section of the river by biologists of the 

 Fisheries Research Institute, who were working 

 near the native village of Igiugig at the outlet of 

 Lake Iliamna. However, no pink salmon spawn- 

 ing surveys were performed on the Kvichak River 

 prior to 1958. Surveys of red salmon spawning 

 grounds in streams tributary to Lake Iliamna re- 

 vealed no spawning pink salmon populations. No 

 observations were made in the tidal area below 

 Kaskanak Flats. 



On the basis of catch data and timing of 

 the run, it is apparent that the 1958 pink salmon 

 run to the Kvichak River escaped the commercial 

 fishery almost entirely. Only about 11,000 pink 

 salmon were deliveredto the cannery at Koggiung 

 after the close of the red salmon season in late 

 July. 



Personnel of the Fisheries Research Insti- 

 tute made the following observations on the pink 

 salmon escapement from September 9 to 12. 



Number present 



An accurate estimate of the total number of 

 pink salmon could not be made because only one 

 channel of Kaskanak Flats was surveyed, covering 

 the navigable section of the river from Igiugig to 

 Ole Creek. In this area alone, 10, 000 to 15, 000 

 pink salmon were spawning- -one or two pairs of 

 fish per ten square feet of gravel. If it can be 

 assumed that pink salmon were present in simi- 

 lar numbers throughout the flats, then the spawn- 

 ing population in the Kvichak River in 1958 would 

 probably have been between 150, 000 and 250, 000. 



Time of spawning 



On September 9, the time of the main sur- 

 vey, most pink salmon were paired on the grounds 

 and actively spawning. The survey disclosed only 

 occasional small groups of schooled fish. White 

 fungus patches were present on about 50 percent 

 of the live fish, and there were only a few dead 

 salmon. This evidence indicates that the survey 

 was made just after the peak of spawning. 



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