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<br />obtained with fingerling coho salmon after 2 years in a <br />hatchery pond (Phinney and Matthews 1973). Pigment <br />retention in coho smolts after 2 years in the wild, <br />however, was only about 68% (Gray et ale 1978). Pigment <br />retention of adult chinook salmon marked as fingerlings has <br />not been fully investigated, although Evenson and Ewing <br />(1985) report 50-60% mark retention after 4.5 years in <br />chinook salmon marked as yearlings. Long-term effects on <br />growth and survival have not been evaluated for spray- <br />marked fingerlings. <br />This study evaluated fluorescent pigment marking as a <br />tool to identify stocks of chinook salmon as they returned <br />to French River in spawning runs. We determined whether <br />chinook salmon marked as fingerlings still retained <br />identifiable fluorescent pigment when they returned as age <br />2+ to 5+ adults; we quantified pigment concentration in <br />adult chinook; we identified body locations most likely to <br />retain pigment granules; and we determined the effect of <br />fluorescent pigment spraying on survival and growth in Lake <br />Superior. <br /> <br />METHODS <br />On 9 May 1984, over 5l,000 chinook salmon fingerlings <br />(approximately 50 mm total length) were spray-marked with <br />red fluorescent pigment. Details of pigment application <br />are described by Bandow (l987). After 33 d, the right <br />pelvic fin was removed from lO,lOl of the spray-marked fish <br />and the left pelvic fin from 10,092 unmarked control fish <br /> <br />3 <br />