growth rates are comparable to those measured in situ (H. uninervis,
0.15–0.27 mg shoot1 d1; T. hemprichii, 0.24–0.9 mg shoot1
d1) in winter from the four monitoring sites described above (C.
Collier, unpub.). The exception was C. rotundata which had lower
growth rates than those recorded in situ (1.3 mg shoot1 d1),
but data for only one site (Green Island) is available. Leaf growth
was not significantly affected by the 35 C temperature increases
but there was a significant difference in growth between species
(p < 0.001 Table 1) with growth being fastest in T. hemprichii followed
by C. rotundata and slowest in H. uninervis. In the 40 C
experiment, growth was significantly (p < 0.001) reduced in the
40 C treatment compared to ambient water temperature for all
species (Fig. 2). Growth rate was the most affected in H. uninervis
(88% reduction) followed by T. hemprichii (63%) and C. rotundata
(51%)