COMMENTS ON 'EVALUATION OF CAUSES FOR THE 



DECLINE OF THE KARLUK SOCKEYE SALMON RUNS 



AND RECOMMENDATIONS FOR REHABILITATION,' 



BY R. VAN CLEVE AND D. E. BEVAN 



George A. Rounsefell' 



The causes for the decline of the Kaiiuk River 

 sockeye salmon runs are many and diverse. Van 

 Cleve and Bevan oversimplify the case, stress- 

 ing but a few factors and ignoring others 

 without adequate explanation of their omission. 

 Their paper also contains several obvious mis- 

 statements, e.g., 



deleterious effects on survival of low autumn (11 out of 

 48 years) and late spring (about 14 out of 47 years) 

 temperatures, survival depends to some extent on the 

 season of spawning. It would be best then to abandon 

 the idea of obtaining a spring and fall group of spawners, 

 but rather to encourage the canning of the early and 

 late fish, and insist on a higher percentage of the sum- 

 mer fish being in the escapement. . . . 



Rounsefell in 1958 was apparently unaware of the 

 work of the International Pacific Salmon Fisheries 

 Commission on the Fraser River sockeye that had re- 

 vealed the peculiar life history of several of the largest 

 runs in that system which spawn below the lakes where 

 the young are reared so that the fry have to migrate 

 upstream into the nursery lakes .... 



In my report (Rounsefell, 1958:85), I speci- 

 fically refer to this habit in the sockeye salmon 

 that spawn below both Chilco Lake and Babine 

 Lake. On the same page I refer to Philip Nelson 

 observing the young of these river spawners at 

 Karluk working upstream through the weir 

 pickets. This habit was well documented long 

 before the Salmon Commission existed. 



Again they state, 



. . . there is now no reason for support of Rounsefell's 

 assumption that all segments of the run interbreed, i.e., 

 that escapement from any part of the run is equally 

 desirable. 



On page 147 of my report I state. 



They state that the estimate of 400,000 sock- 

 eye salmon spawning in Karluk River in 1926 

 is " . . . more fish than were recorded for any 

 other part of the watershed." If the 400.000 is 

 compared with the 1926 escapement of 

 2.500.000 it comes to only 16% compared with 

 84% in the lake and its tributaries. I assume 

 that Van Cleve and Bevan are not trying to say 

 that while those that enter the lake consist of a 

 large number of subpopulations. the river 

 spawners are only one subpopulation. If they 

 do mean this they obviously invalidate their 

 comments about the Birkenhead River si)awn- 

 ers consisting of different races spawning along 

 the same stream at different distances frcm its 

 mouth. Rich (Gilbert and Rich. 1927:23) states 

 on 18 July 1926 that 



.... Any estimate of the number of spawning fish 

 was difficult but it was thought that certainly not less 

 than 300,000 fish, and probably about half a million, 

 had entered Upper Thumb River up to this time. 



.... On the average, neither the very early nor the 

 very late spawners are as successful as those spawning 

 in midseason. The analyses showed that because of the 



' University of Alabama and Marine Environmental 

 Sciences Consortium, Dauphin Island. AL 36528. 



Manuscript accepted February 1973. 

 FISHERY BULLETIN: VOL. 71. NO. 3. 1973, 



This was far too many spawners for the ex- 

 ceptionally dry year of 1926, and the returning 

 progeny numbered only 1,460.000. This can 

 be compared with the 1931 escapement of only 

 870.000 which produced a return of 2.600.000, 

 with but 22% of summer spawners. 



Van Cleve and Bevan also state, 



651 



