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

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Some growing on crevices on the southern survived for 12
months, but: even
No D. antm>ctica colonised either of the at Tautuku
where barnacles had been away. Porrphyru columbina becm'lle
established on both Area E.
barnacles do not appeal:' to
D. antm>ctica
up the shore, it is that mussels ulay do so.
Paine (1971) noted that at
a band of Pel'YUl canaliculus was
~rh.is
from the D.
band by a zone of mixed
zone is
free from mussels (Fig. 4.1a) and
O'l'leS its origin to the starfish austl"a which preys
on Perna. According to paine, small antapctica colonised this
mixed species zone, but did not survive there. It is not clear
if were burnt the summer, or eaten.
removing the starfish, and the starfish the kelp, and
then
the downshore spread of the mussel. Unfortunat.ely,
he did not away the mussels to see if the would
up the shore. An along these lines could usefully
determine whether the upper li.mit: of the kelp is in any way influenced
by the mussel.
The zonat.ion pattern at Woodpecker Bay (Fig. 4.Icl is the
reverse of that at Anawhata, in that the band is often above
the In this situation it that the
mussel might induce the kelp to spread to slightly lower levelso
Grazing by fish may be one of the main reasons ~lhy D.
does not grow in the sublittoral. In a sward of young
D. antarctica at Kean Point all the plants between MLWS and ELWS
were eaten by fish, and at Ohan Point a distinct graze line was
visible at about MLWN. The green bone or butter
(Co1'idodax puZlus, Bloch and appears to the
grazer on Durvillaea On the Kaikoura coast,
(PseudoZabrus spp.) may also be Dnportant.
If fish is a factor
the lower of
D. arise: the fish do not graze
the full width of the band at tide, and how small D.
wiZlana manage to survive in the sublittoral where
is
intensive?
The
set a
graze line
upper 1 imi t to
at Ohau Point
butterfish in this aJ:'ea a:r:'e
Near Bethel1s Beach.
that.
At 101.11 tide,
and 'thus