Landscape:BBC
NHU;
dver:
Espen
Rekda
/BBC
NHUBBC Wildlife December 2019
WALRUSES
Gentoo penguins, found
on the Antarctic Peninsula
and subantarctic islands,
gather on an iceberg before
heading out to sea to feed.ANTARCTICA
he southernmost continent in
the world is the fifth largest. About 98
per cent of it is covered permanently
by ice with an average thickness of
1.9km. Yet, despite all that ice and
with little more than 100mm of
precipitation per year, Antarctica is
technically a desert, the largest on
Earth. It is, however, cold... very cold!
The coldest air temperature ever
recorded by conventional means was
–89.4°C at Russia’s Vostok Station
in July 1983, but sensors mounted
on satellites have located even colder
temperatures. On the East Antarctic
Plateau ground temperatures regularly
reach –98°C during a polar winter
night, the coldest place on the planet.Living on the edge
As ice dominates life on the Antarctic
mainland and in the surrounding
Southern Ocean, it is a challengingplace for living organisms to survive,
but survive they do, with the snow
petrel and Antarctic skua breeding the
furthest south of any animal. They
nest on rocky outcrops that stick out of
the ice, some sites up to 440km from
the sea. Aside from emperor, chinstrap
and Adélie penguins, which nest on
Antarctica, there is precious little
else. Residents are no bigger than
mites, nematodes, springtails and
water bears, along with algae, fungi,
lichens, mosses, liverworts and a
couple of small plants, mostly on
the Antarctic Peninsula.
Sea-ice surrounds the continent,
doubling its size as the sea freezes in
winter. Under that ice is a completely
different world, where invertebrates
reign supreme. The Seven Worlds
team dived below the ice in McMurdo
Sound, the southernmost navigable
body of water, and found the seaT
“One major problem was to not get lost whilst
diving below the ice in McMurdo Sound,” says
producer Fredi Devas. “A large hole was cut in
the ice to enable the divers to enter the water,
but they didn’t have ropes to help them find
their way back. A tangle could have been
fatal, so the topside team scraped arrows in
the ice that were backlit by the sun and so
could be seen from below. In this way, the
underwater cameramen could follow the
arrows and find their way back safely.”FIELD NOTES
EpisodeproducerFredi
Devasontheperilsof
lming under the ice.