VREELAND ET AL.: HOMING BEHAVIOR OF MARKED COHO SALMON 



Table 1.- Weight, number, and marks of 1968-brood coho salmon 

 examined by sample day during the 1970 Youngs Bay gill-net 

 season.' 



Table 2.-Number of 1968-brood LV- and RV-marked coho 

 salmon recovered by year, area, and fishery, 1970 and 1971.' 



Date 

 1970 



Weight 

 (kg) 



Marks 



Number 



LV Ad-LV Ad-RV Ad 



1 — 



1 1 1 



'The sampling was done at New England Fish Co. unloading 

 dock. 



1968-brood LV- and RV-marked coho recovered by 

 year, area, and fishery. 



The returns of Klaskanine, Big Creek, Grays 

 River, Elokomin, and Little White Salmon 

 hatcheries were examined for LV- and RV- 

 marked 1968-brood coho salmon. A total of 9,039 

 jacks returned to Klaskanine Hatchery and 8,705 

 were examined for marks. Only three LV and no 

 RV marks were observed. No LV or RV marks 

 were found in the returns to the other three 

 hatcheries. At Little White Salmon Hatchery, 1 

 LV-marked and 55 RV-marked coho were ob- 

 served. Table 3 lists the number of marked 1968- 

 brood coho returning to the five previously men- 

 tioned hatcheries by hatchery, year, and mark. 



1971 Sampling Season 



In 1971 the sampling for marks was done at 

 Barbey Packing Corporation, Astoria, Oreg. The 

 entire catch of coho salmon was examined on 27 

 days of the 49-day season. The catch of 1968-brood 

 coho was estimated to be 8,110 fish. Of these, 5,477 

 were examined for marks for a 67.5% sample. Ta- 

 ble 4 shows the days sampled, the weight and 

 numbers of coho sampled, and the marks found. A 

 total of 355 marked coho were observed, of which 

 336 were LV marked and 8 were RV marked 

 (Table 4). Length and weight data were collected 

 from 320 of the marked 1968-brood coho examined. 

 These data are presented in Table 5. 



The sport fisheries of Youngs Bay and its tribu- 

 taries were not sampled in 1971, but the Fish 

 Commission of Oregon again sampled the Colum- 

 bia River gill-net fishery for marks. A total of 17 



'Columbia River and ocean sport and ocean commercial fish- 

 eries were not sampled for these marks. 



Table 3.-Number of 1968-brood LV- and RV-marked coho salm- 

 on recovered at five Columbia River hatcheries by year, 1970 and 

 1971. 



LV-marked and 74 RV-marked 1968-brood coho 

 salmon were recovered. As in 1970, the Columbia 

 River sport, California, British Columbia, and 

 Alaska ocean sport, and ocean commercial 

 fisheries were not sampled for LV- or RV-marked 

 coho. 



Hatchery returns examined in 1970 were again 

 examined in 1971. Klaskanine Hatchery had an 

 adult coho return of 5,476 fish. Only one LV- 

 marked and no RV-marked fish were found. No 

 RV- or LV-marked adults were seen at Big Creek 

 or Elokomin hatcheries, and only one RV mark 

 was recovered at Grays River Hatchery. At Little 

 White Salmon Hatchery, 300 RV-marked and only 

 3 LV-marked 1968-brood coho were recovered. (See 

 Table 3.) 



The estimated catches of marked 1968-brood 

 coho salmon by fishery, year, and mark are 

 presented in Table 6. These values were obtained 

 by multiplying the total 1968-brood coho catch for 

 a fishery by the rate of occurrence of a mark in that 

 fishery. Columbia River gill-net estimates were 

 calculated for weekly periods and summed for the 

 season. The Youngs Bay marked fish estimates 

 were made for the entire fall season. For example, 

 it was estimated that 8,110 1968-brood coho were 

 caught in Youngs Bay in 1971 (Table 4). Of these 

 fish 5,477 were sampled for marks and 336 LV 

 marks were observed. Thus the estimated catch of 

 LV marks was 8,110x336/5,477 = 498. 



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