F
OR ME, Australia
is a sacred being,
nourishing a
multitude of creatures
that rely on her bounty
for their existence. I
feel privileged to be old
enough to have seen some
of her special places when
they were still largely
unscarred, and I’ve always
felt pride in how AG
brings the wonder of our
country home to those
who may not be able to
experience it firsthand.
Every now and again,
we publish an issue with
special meaning for me.
The stories on the Wessel
Islands and the dugongs
in this edition awoke vivid
memories of childhood
experiences on Cockatoo
Island in WA’s Buccaneer
Archipelago, and sent my
mind back many decades
to that magical place. Its
waters nurtured a giant
coral garden crammed
with life. It was common
to see acres of sea churned
to foam by feeding fish or
great schools of belly-
flopping mantas.
Despite my conscience,
I still feel a thrill when
I remember being taken
by Aboriginal people on
traditional dugong and
turtle hunts. Out on the
water in a tiny dinghy,
oars muffled with hessian
sugar bags, I would sit on
the stern thwart behindthe oarsman, hardly
daring to breathe, for I’d
been told dozens of times
that dugongs and turtles
can hear us.
The spearman stood
in the bow, weapon at
the ready and silently
indicated the direction
the boat should take
by the tiniest shifts of
his body. “It seen h’our
shadow move too, boy,”
I was told. He dropped
one shoulder: “left”; then
both: “slower”. Another
shrug and the oars were
stilled, the dinghy drifting
above the seagrass. The
initiation scars on his
shoulders rippled as
he tensed, and then –
thwisssht – away went the
spear. Harpoon in the
quarry, the line hissed
out and the dinghy raced
through the water until
the dugong or turtle tired.
The hunter then hurled
himself overboard to
secure the catch, which
was dragged to the dinghy
and quickly killed. Later,
I was given a bit of meat
to take home to Mum for
“bein’ such a good luck”.
It may prick my
conscience now, but it
wasn’t my childhood
heroes who brought these
species to their parlous
state. It also reminds
me that I owe much to
our beloved land and its
indigenous peoples.WITH FR ANK POVAH
A DEBT OWED
What do ants do in the winter? Where I live in
Tasmania , I never see them during the winter.
CLEA EYKELKAMP, TAMAR RIVER, TASMANIAPROFESSOR ALAN ANDERSON,
CSIRO DARWIN LABORATORIES, SAYS:
The activity of ants in cool-temperate regions, such as Tasmania, is
highly seasonal. Most species prefer high temperatures and so have
low activity during colder months; they just stay inside the nest.
The times of the day that ants forage can also be highly seasonal.
During colder months most foraging occurs during the middle of
the day. In summer this time of day is often too hot for foraging,
so most activity occurs in the early morning, late afternoon, or at
night. Some species forage only during the night (nocturnal) in
summer and only during the day (diurnal) in winter. One Tasmanian
species – Hickman’s epaulet ant – is remarkably adapted to the cold
in that it forages only at night during the colder months!Q
A
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“Why is Australia so rich in opals?”
VAL SMITH, PADSTOW, NEW SOUTH WALESPROFESSOR PATRICE REY,
UNIVERSITY OF SYDNEY, SAYS:
Almost 90 per cent of the world’s opals are found in central
Australia. There are several reasons for this. Opal generally
forms within 20m of the surface in a silica-rich
gel. Around 100 million years ago, a vast sea
that covered 60 per cent of Australia – from
Coober Pedy in the south to the Gulf of
Carpentaria in the north – began retreating.
This drying out increased acidity levels at
shallow depth, releasing silica through the
weathering of sandstone and causing the
formation of common opals in the resultant silica-
rich gel. Further weathering lowered the acidity again, allowing
precious opal to form. The vibrant colour in precious opal comes
from the refraction of light through
regularly arranged silica spheres. The
spheres in common opal are less
regular in pattern and diameter,
which results in a duller colour.A
Q
PHOTODIGITAAL.NL/SHUTTERSTOCK; TORSTEN BLACKWOOD/GETTY
January-February 2014 127