Laserfiche WebLink
<br />All statistical analyses except the Chi-square test were <br />computed with SYSTAT (Wilkinson 1988). <br />RESULTS <br />A total of 54 pelvic-clipped chinook salmon returned <br />in spawning migrations to French River from 1986 to 1989 <br />(Table 1). Proportions of spray-marked versus control <br />fish were not significantly different between years <br />(X2 = 6.73, df = 3, P >0.50), but significantly fewer <br />marked fish returned than control fish (X2 = 5.35, <br />df = l, P <0.025). <br />Pigment granules retained their bright color <br />throughout the experiment, but often only one to four <br />granules remained per fish. Determining the location of <br />granules was often confounded by fluorescing unembedded <br />extraneous material, so identification of granules <br />sometimes took over a minute. Pigment was retained by a <br />higher percentage of females (87.5%) than males (62.5%) <br />(Table 2), and more granules were found per female than <br />male. <br /> <br />The length-weight relationships (Table 4) at the time <br />of capture for spray-marked versus control chinook salmon <br />were not significantly different (ANCOVA, test of adjusted <br />intercepts, P = 0.l82). There was no significant mark or <br />sex effect on length at ages 1, 2, or 3 (P >0.05). At age <br />4 the mark*age interaction was marginally significant <br />(P = 0.045). The back-calculated lengths at age (Table 3) <br />for each mark (spray-marked and control) and sex group were <br /> <br />5 <br />