The Prince Edward Islands
(PEI) are a South African territory in the South Indian Ocean, about 2000 km
southeast of Cape Town. This island
group comprises two sub-Antarctic islands, Marion and Prince Edward that are
actually two peaks, about 20 km apart, of a large volcano rising out of the sea
bed. Over the last four years I visited
these islands three times to collect material for Tshoanelo's PhD study. She is researching the systematics and
biological antifreeze attributes of several benthic species residing in
habitats around the islands, ranging from shallow inshore water to about 500 m. One of these species is the bullhead notothen
(Notothenia coriiceps), a shallow water species that was common in the
1980s, but seems to have disappeared as we have not found it since the
beginning of the project in 2009. Trying
to find this species was the main objective during this year's trip to the
islands, during April-May, either by collecting or observing it in its
habitat. Collecting methods included
fishing from a small boat and dredging (towing a large metal cage along the
bottom) from the ship. Observation
methods included snorkelling and, for the first time, underwater video
photography. Snorkelling has the
advantage of covering a relatively large area, but one cannot swim (in a thick
wetsuit) in the islands' cold water (7°C) more than 20 minutes. By contrast, the underwater video camera
filmed continuously for over 2 hours, but it was stationary. So the two methods complemented each
other. As I anticipated we did not find
the bullhead notothen and the reasons for its potential disappearance will be
discussed at an international conference in July. Nevertheless, the dredging yielded species
that are of interest to the project as well as a juvenile of the spiny horse
fish (Zanclorhynhcus spinifer).
The latter is the second specimen and the first genetic sample of this
species collected at the PEI.
This year's visit to the
Prince Edward Islands was also the last voyage of the SA Agulhas, the
supply and research vessel that serviced South Africa’s Antarctic and
sub-Antarctic bases since the mid-1970s.
A short official ceremony to commemorate this voyage took place at the
South African National Antarctic Programme building at the V&A Waterfront on
the morning before the ship sailed. At
the same time the new vessel that will replace the SA Agulhas was on its way to South Africa from the shipyard that
built it in Finland. When I returned
from the PEI, the new vessel had already docked in Cape Town and I was
fortunate to have a tour of it. I was
impressed. Presently named SA Agulhas II, this ship is larger and
more specious in internal design. It has
a larger hangar and landing deck for the helicopters. All cabins are above water level and none
with more than 2 beds (as opposed to 4 in the old ship). The labs are much larger, equipped with
internet connections and printers, and in the case of the wet lab with more
water connections and basins. The
winches are housed inside the ship which makes operations in cold and/or rough
conditions easier. There is also a ‘Moon
Pool’, a well in mid-ship that opens to the water through the bottom of the
ship and will serve as the launching area for oceanographic equipment when
working in pack-ice. While the ship is
also equipped with an A-frame it does not have a slipway and so will not be
able to launch bottom trawls. Unfortunately,
this means limited capacity for fish work.
I placed a brochure of the new ship at the library for all to see.
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| Marion Island Base |
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| SA Agulhas II |
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