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

80
algae except for those in crevice and rockpool refugiao These
islands lie south of the mean extent of the Antarctic pack ice in
winter, and its maximuln extent In summer' •
(iv) Gough I.
D. antarctica grows abundantly. Photographs in Chamberlain
(1965) clearly shm1 a continuous D. antaretiea band such as occurs
in southern Net·] Zealand,
(v) Tristan da CUnha (Fig. 4,2c,d)
There is no DuY'ViZZaea on these islands. In photographs of
the lower littoral sent to me by Mr Gavin Jack, the agricultural
superintendent for the islands, only Lam ina ria sp. was visible.
Specimens of a plant which the islanders called "bull kelp" and which
were sent to me, were Laminaria paZZida. MY R. Siffions, South African
Governmen"t Marine Phycologist , has no record of Du~iZZaea drifting
to Tristan cia Cunha.
(iv) Bouvet I.
Little information about this island is available. In his
summary of the Antarctic Voyage, Hooker (lB44:vii-ix) reported drifting
Durvillaea near Bouvet I. and further south (61°S) when Sir James
Clark Ross tried unsuccessfully to sight the island. Scientists
first landed in 1927 as part of the Norwegian Scientific Expedition,
but unfortunately no account of the algae was published.. Holdgate's
(l968) account of the flora is restricted to terrestrial plants.
Several clear photographs of the coastline appear in Holtedahl (1935) 0
These were taken in the 1927-28 summer and show small glaciers reaching
the sea in several places. Plates 48 and 49 show that there is no
seaweed of any size growing in the littoral near th~ landing place.
Other plates show a line of drift ice on the beaches at high tide
mark, and some floating ice. Even in summer the littoral must be
eXfOsed to "the abras i ve ac tion of dr ift ice. Holdga te stated in a
letter (7 August 1974) "From the general nature of the hobita,t and
evident cold conditions prevailing around the island I would be somewhat
surprised were this seaweed [D. antarctica) to be found there".
See H.O, Pubn. No .225 U.S. Naval Oceanogrph. Office Washington.