Pearcy et al ' Oncorhynchus clarki clarki and O mykiss off Oregon and Washington 



701 



Tag recoveries 



Two of the cutthroat trout tagged with Floy tags on 

 our cruises in 1985 were recovered by fishermen, one 

 43 days after release 72 km south of the tagging loca- 

 tion and the other 290 km south of the tagging loca- 

 tion (Table 4). We also caught four hatchery coded-wire 

 tagged steelhead smolts in the ocean 17-74 days after 

 hatchery release. The two released in the Clearwater 

 River, Idaho, were captured close to the mouth of the 

 Columbia River where they entered the ocean. Two fish 

 released in the Quinault River, Washington, were 

 recovered 85 km and 269 km south of where they 

 entered the ocean. Movements to the south by these 

 two steelhead and the cutthroat trout may have been 

 related to advection of surface waters during the 

 upwelling season (Pearcy and Fisher 1988). 



(.)f the eight maturing steelhead tagged, one (445 mm 

 FL) tagged off Cape Disappointment near the mouth 

 of the Columbia River was recaptured 79 days follow- 

 ing its release at 495 mm FL in the Columbia River. 

 Its growth rate between release and recapture was 0.63 

 mm/day. 



Age, lengths, and sex ratios 



Of the 110 cutthroat trout with readable scales, 32%. 

 45%, 19%, and 3% migrated to sea for the first time 

 after one, two, three, and four winters in freshwater 

 (ages 1., 2., 3., and 4.)*, respectively (Table 5). This is 

 a younger age distribution than found by Giger (1972) 

 for wild cutthroat trout from coastal Oregon river 

 systems, but similar to that found by Loch and Miller 

 (1988) in the ocean off the Columbia River mouth. Most 

 of the age 1 . cutthroat we caught probably originated 

 from hatcheries (Loch and Miller 1988), including 

 hatcheries on the Columbia River. 



Most cutthroat were immature or maturing fish on 

 their first ocean migration (age .0). Only eight fish had 

 scales that showed evidence of reduced growth (a 



* Age designation follows that recommended by Koo (1962), and used 

 by others (Godfrey et al. 1975, Hartt and Dell 1986), where the 

 numbers before and after the decimal point refer to winters spent 

 in freshwater prior to first migration to the ocean and winters spent 

 in the ocean, respectively. Ages 1., 2., 3., etc. designate the fresh- 

 water age of a fish without reference to its ocean age. 



