Survivorship
Despite experiencing extreme thermal anomalies and grazing rates at the start of the experiment, cool-warm transplants displayed high survivorship (number of surviving rhizome fragments) with no significant differences observed between treatments at the end of the thermal stress period (χ2 = 10.65, df = 5, p = 0.06, Fig. 3). Survivorship then declined in all treatments over winter months (between October and April), potentially due to dislodgement from storms. Notably however, both centre-centre and centre-warm treatments displayed significantly lower survivorship than all cool-edge and warm-edge populations by the end of the experiment (χ2= 58.07, df = 5, p<0.001, Fig. 3A).
The number of living shoots per fragment of rhizome was relatively stable over time, with slight declines over the period of thermal stress (Fig. 3B). Warm-warm and cool-centre treatments displayed significantly lower rates of shoot mortality than central and other cool-edge treatments at the end of the thermal stress period (ANOVA, F(5,388) = 8.118, p <0.001). By the end of the recovery period, changes in shoot numbers on the surviving fragments had stabilised and cool-centre fragments had recovered to display no net change from the beginning of the experiment.