Table 4.7: Effect of larval experiences on Evechinus chloroticus size at settlement: (A) radial length and (B) spine/body ratio (SBR), analysed using ANCOVA on mixed effect models. SBR was logtransformed to meet ANCOVA assumptions. Significant effects (p < 0.05) are highlighted in bold; p values are based on the chi-square statistic.
Final radial length at 38 d post-settlement was significantly higher at all copper levels in the Water treatment (One-way ANOVA: F(3,7) = 14.41, p = 0.002; Coefficients contrasts: in all cases p < 0.03). Juveniles were nearly two times larger at ANZECC levels than in controls, more than 1.5 times larger at the High Pulse level and 1.3 times larger at High Chronic levels (Figure 4.6a). In contrast, in the Diet + Water treatment, juveniles were smaller with increasing copper exposure (One-way ANOVA: F(2,4) = 8.08, p = 0.04), with juveniles at both copper levels approximately 1.5 times smaller than controls (Coefficients contrasts; in all cases p < 0.04); no significant differences was observed in the Diet treatment.