number of fish migrating may have been affected 

 by the trawl fishery which could have removed 

 potential migrants. 



Cass et al. (1983b) reported results from tagging 

 2,997 lingcod off the west coast of Vancouver Island, 

 BC, and 752 in the Strait of Georgia, BC, in 1978. 

 However, the combined recovery rate through 1982 

 was so low (1%— apparently because of the excessive 

 mortality from too high a dosage of oxytetracycline 

 that was injected intraperitoneally in an attempt to 

 validate aging methods) that little could be con- 

 cluded on movements. Of the 21 recaptures with 

 known recapture location, 4 (19%) had traveled 

 more than 20 km. One of these was caught off cen- 

 tral Oregon, 510 km from the tagging sites. 



Further Canadian tagging efforts off southwest 

 Vancouver Island in July 1982 and in the Strait of 

 Georgia in 1982-83 are reported by Cass et al. 

 (1983a) and Cass et al. (1984), respectively. Off Van- 

 couver Island, 7,429 lingcod were tagged and 1,442 

 (19%) were recaptured through 1982. Very little 

 movement was indicated, since 97% of the recap- 

 tures were taken in the area of release by Canadian 

 trawlers. As with the Reeves' (1966) study, the ini- 

 tial recapture rates were very high because of in- 

 tensive trawling in the tagging area. The Strait of 

 Georgia tagging effort indicated relatively little 

 movement. A total of 3,991 lingcod were released 

 from November 1982 to March 1983 in three areas: 

 Campbell River (76%), Pender Harbor (16%), and 

 Stuart Island (8%). Through November 1983, 392 

 recaptures were reported by sport and commercial 

 fishermen, and location of recovery was known for 

 383 of these. Of the latter number, 354 (92%) were 

 recaptured within 5 km of their release site and 235 

 of these (61%) showed no detectable movement. 

 From these observations the authors concluded that 

 lingcod do not undertake extensive short-term 

 movements. 



We are aware of only one other lingcod tagging 

 study that shows migration similar to that in the 

 present study. H. Horton^ reported results from 552 

 lingcod tagged on the central Oregon coast from 

 June 1978 to January 1982. Nineteen recaptures 

 were reported through 1985: 10 had not moved 

 significantly and 9 had migrated more than 10 km. 

 Of those that migrated, 2 went a distance of more 

 than 100 km. 



Our study gives evidence that certain populations 

 of lingcod have a high proportion of individuals likely 

 to migrate. Large, mature individuals may have 



^H. Horton, Oregon State University, Corvallis, OR 97331, pers. 

 commun. October 1985. 



migration patterns similar to individuals smaller 

 than the reported sizes at maturity. The movement 

 pattern in our tagged sample was directional, not 

 random. In assuming that the fraction of total re- 

 captures more than 8.1 km from the tagging site 

 represents the migration within the population, we 

 also assumed that migrating lingcod had fishery ex- 

 ploitation rates similar to those that did not migrate. 

 Since lingcod are highly valued, they attract com- 

 mercial and/or recreational fishing in virtually every 

 known area of concentration. The ranges in recap- 

 ture rates were narrow among years (Table 2), 

 among tagging locations (Table 3), and between 

 sexes (Table 5), suggesting that the probability of 

 recapture was independent of migratory behavior. 



Acknowledgments 



Washington Sea Grant supported this research 

 under several grants. We are indebted to Donald 

 "Bud" Carlson, skipper of the commercial troller 

 Paul Revere, for his help in capturing and his knowl- 

 edge of lingcod habits. Several individuals with the 

 Washington Department of Fisheries helped with 

 tagging and tag recovery processing, including G. 

 Bargmann, J. Beam, K. Swenson, and K. Stick. 



Literature Cited 



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 Cass, A. J., G. A. McFarlane, K. Rutherford, and I. Barber. 

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