Evening star., 1941-05-04
Reports Findings
Of CoroI Study
Bv Frederic J. HdSktn.


was the recent completion of the Great
Barrier Reef expedition on Low Island,
North Queensland, Australia, after
spending a year studying the largest
coral reef formation in the world The
Great Barrier Reef. with only occasional
breaks, is a majestic coral rampant over
1900 miles long Although it has been
described as the greatest breakwater
in the world, this must be qualified, for
it consists of innumerable reefs running
largely parallel to one another and
overlapping except at rare openings.
Within the deep-water channel
between the barrier and the coast are
scattered a multitude of islands some
large, high and rocky, and others, of
coral origin, small fat and sandy. Low
Island is of this latter type, and lies
midway between the barrier and the
mainland. some Is miles apart. 1t
really consists Of two wooded islands
distinguished from others by the pres
ence, on the smaller of the two, of a
tall white lighthouse which shines
clearly in the bright tropical sunlight.
Here were erected the hutS in which
the members of the expedition lived,
and these four acres of sand were for
year q most densely populated place.
At low tide the reef uncovered far
and wide, and 1t was possible for mem
bers of the expedition to walk from one
island to the other on the exposed coral
fiat beyond. This exposed area formed
perfect collecting ground and experi-
mental station, and probably no similar
extent of coral reef has ever been so
intensely studied.
Besides smaller boats, the expedition
had the use of a powerful motorboat
some 40 feet long and from this at
regular weekly intervals were taken
samples of sea water at various depths,
and of the microscopic drifting plant
and animal life in the sea. The former
were obtained with an instrument called
the insulating water bottle, let down
to the required depth, followed by a
metal messenger" This, on hitting
the top OF the bottle, released a spring
which Immediately closed the bottle,
This was then drawn up, the tempera-
ture read, and the water drawn off to
be later tested for a variety of SUBJ
stances. The minute life of the sea
was collected in conical nets made Of
fine silk, which were let down to certain
depths and then drawn up. Samples
of the catches were examined. and the
number of the different plants and
it was possible to say to what extent
the numbers fluctuated during the year.
The purpose of the expedition was to
study the conditions under which corals
live. Corals are not to be regarded
as animals having nothing to DO with
the other inhabitants of the reefs and
independent of the conditions in the
sea, but ss, the most conspicuous MEM
bers of a special type Of community
life called a coral reef.
Corals are essentially the same as
formations so common on rocks around
coasts. But instead of living each in
dividual free and unto itself, corals
usually form in great colonies, and all
produce massive, linly skeletons. 1t Is
these, dried and bleached white, which
fill so many cases in museums. In life
they are covered with delicately- -colored
living tissue, which from innumerable
fine openings project soft. tubular
bodies, each surmounted by a ring OF
tentacles irclosing a mouth. This soft
body is highly sensitive and retracts at
the slightest provocation. The majority
of corals expand only at night, when
alone they can be studied. The deli
cate teEtacles which wave so graciouSly
in the water are really deadly weapons,
for they contain batteries of sting cells,
and the little animals which touch
them are paralyzed.
For generations the food and feeding
of corals has been a subject OF keen
interest. The question among scientists
is whether coralS feed solely on the
minute animals in the sea or II they
have other nourishment. The tissues
of most corals are packed with minute
brown bodies which are really plants.
They flourish within the coral, but
their function remains mystery. Many
have thought that corsls feed upon them
when there is no other food, and that
the corals, as 1t were, cultivate them so
as to tide over when other feeding SUBJ
stances are scarce. Studies on Low
Island gave little support to this
ingenious theory.
Collecting of specimens from the reef
and also from the sea bottom, the latter
by means of dredges and travis, took
much time, but just as important was
the collection of information as to
where they lived, in what numbers and
in what company. Low Island and
other reefs were surveyed, not only by
geographers, but also by biologists OF
the expedition.
The popular belief that a reef is a
wonderland of beauty is largely in
correct The exposed surface is usually
a desolate area of dead coral fringed
with large boulderS, and with scarcely
a trace of color other than occasional
patches of weed. 1t is only in deep
pools or of the edge of the reef during
very low tides that the beauty of the
coral is exposed. Then are revealed
corals of every color and shape, with
fish OF the most vivid hues and fan
tastic shapes dsrting among them, the
delicate, projecting tentacles of worms
and the brightly -colored frilled tissues
of clans, both of which burrow into
the coral, adding their quota to the