Fishery Bulletin 88(4), 1990 



Thirteen were recovered on Canadian trawl grounds 

 including La Perouse Bank (8) and Swiftsure Bank (4). 

 Twenty of the migratory recaptures occurred within 

 the tagging area between Makah Bay and the Sekiu 

 River (Fig. 1), and 12 recaptures were made east of 

 the study area in the Strait of Juan de Fuca. 



Of fish with known sex and recapture location, a 

 higher proportion of male Iingcod were migratory as 

 compared with female Iingcod. Of 311 male recaptures, 

 66 (21.2 %) were judged to be migratory, while 4 of 

 51 female recaptures (7.8%) were considered migratory 

 (Table 4). The null hypothesis that male and female 

 recaptures were equally likely to be migratory was re- 

 jected (r = 4.20 withl df; P = 0.0402 with Yates 

 correction). 



The time span between tagging and recapture for all 

 recaptured Iingcod averaged 237.6 days and ranged 

 from 6 to 1197 days (Table 5). The null hypothesis that 

 the average time span between tagging and recapture 

 was the same for fish recaptured at rlifferent distances 

 was not rejected (F^sm = 1-50; P = 0.2240). 



Discussion 



This study gives qualitative evidence that a portion of 

 the nearshore Iingcod population in the vicinity of Neah 

 Bay is vulnerable to the offshore trawl fishery; how- 

 ever, fishery tag recapture data, unadjusted for dif- 

 ferential fishing effort, are inadequate to make quan- 

 titative statements about the net mixing rates of fish 

 between areas. Clearly, from a harvest management 

 perspective, it is important to know whether offshore 

 stocks of Iingcod contribute to nearshore recruitment, 

 or vice versa, since valued fisheries operate in both 

 areas. 



Previous studies in the Strait of Juan de Fuca and 

 Strait of Georgia have reported variable Iingcod move- 

 ment and indicate some exchange between inside and 

 outside waters. Hart (1943) observed that fish tagged 

 in the vicinity of the Strait of Juan de Fuca and Sey- 

 mour Narrows made more extensive migrations than 



fish tagged in other adjacent inside waters. Of 1993 

 fish released during 1939-43, 209 were recovered of 

 which 34 (16%) traveled distances >8.1 km (5 miles). 

 For 342 recoveries from tags released in the Strait of 

 Georgia during 1943-54, 73 (21.3'Fn) were recaptured 

 within 1.6 km (1 mile) and 32 (9.3%) were recaptured 

 >8.1 km from the point of release. Of those recaptured 

 >8.1 km, the average time at liberty was 3 years and 

 the net movement was northwesterly within the Strait 

 (Chatwin 1956). Mathews and LaRiviere (1987) re- 

 ported that of 1692 Iingcod tagged during 1976-81 in 

 the eastern Strait of Juan de Fuca and in the vicinity 

 of the San Juan Islands, 74 (49.6%) of 149 fish re- 

 covered moved >8.1 km and were judged to be migra- 

 tory. Most recaptures were south or west of the tag- 

 ging site; the predominant pattern of movement was 

 south and west through the Strait of Juan de Fuca. Fish 

 tagged in the eastern Strait of Juan de P\ica migrated 

 more than fish tagged in the San Juan Islands. Five 

 recaptures were reported from the Pacific Ocean. The 

 longest movement to the northeast was to Porlier Pass, 

 British Columbia; the longest movement to the south- 

 west was off Newport, Oregon. 



Previous offshore tagging studies have reported 

 some movement between the various offshore fishing 

 banks. Reeves (1966) reported that of 437 tagged on 

 La Perouse (Forty Mile) Bank in June of 1960, 284 



