A biological study of Durvillaea antarctica (Chamisso) Hariot and D ...

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Almost ~lediately
after D. antarctica was cleared, bare areas
and paint-lDee patches of algae Nere covered by a green'-brown
diatomaceous film (predominantly Lycmophora sp.). Some of the
largest foliose red seaweeds, especially gigartines, were soon
detached after clearing, and on areas cleared during the summer, many
algae were bleached by the sun within a fe\-] days of clearing.
Dense regrowth of D. antarctica occurred only on sites cleared
during autumn and early winter. The small plants, which appeared
in the following spring, grew at densities as high as 7 OOO/m2 and
thus formed a lawn-like sward (Figs 9.14a; 901Sb). POl'phYl'a aoZwnbina and
Scytos'['phon 'lOll/en taY'ia al so appeared on these areas (Fig. 9 .14 ),
but were soon overshadowed by the much faster growing, DuY'villaea
plants. No such phenomenon occurred on adjacent control areas.
Since regroll,th on cleared areas corresponded to the period of
gamete release (Chapter 6), it seemed likely that such dense regrowth
was due to large scale recolonisation of D. antaY'ctica germlings in
t