In Chapter 3, the latent effects of copper across two life stages in E. chloroticus –larval and juvenile, were investigated using realistic scenarios of low copper concentration and short pulses of exposure. Organisms were followed for six weeks post-settlement. Stage-dependent toxicity was evaluated by exposing larvae either early (4 – 6 d post-fertilisation) or late (11 – 13 d post-fertilisation) during development, and as young juveniles (25 – 27 d post-settlement). I then tested resistance of the surviving juveniles to a further exposure to the same stressor.