11 
DREDGING OPERATIONS 
By PROFESSOR THOMSON FLYNN, B.Sc. 
On this occasion, as on all others, one 
of the principal objects of the annual 
Easter camp of the Field Naturalists’ 
Club was the collection of zoological 
specimens, with the object of lending 
aid to the elucidation of any problems 
connected with the lower fauna of the 
State. In the accomplishment of this 
object the use of the dredge and the 
trawl plays an important part, and to 
a great extent this is the most fascin¬ 
ating portion of the work, but land and 
shore collecting, as well as surface net¬ 
ting, are to be counted as important 
factors towards attaining the desired 
object. 
The Easter of this year was not the 
first occasion on which the members of 
the club had visited Maria Island. On 
the last occasion (1912) successful dredg¬ 
ing was accomplished in 100 fathoms off 
the coast of the island. 
Other expeditions have dredged near 
Maria Island at various times. Some 
few years ago the Aurora (of the Aus¬ 
tralian Antarctic Expedition) made suc¬ 
cessful hauls in 06 and 1.300 fathoms 
in the open sea. a few miles off Reidle 
Bay. The Commonwealth trawler En¬ 
deavour also explored the waters be¬ 
tween Maria Island and the mainland, 
and last year the members of the Brit¬ 
ish Association for the Advancement of 
Science took part in a scientific excur¬ 
sion to Maria Island, and important 
-collections of sponges and other inverte¬ 
brates were on that occasion made by 
Prof. Dendy and Dr. Tattersall. col¬ 
lections which, it is hoped, will help 
materially in bringing the lower marine 
fauna of Tasmania under the notice of 
British scientists. 
The East Coast of Tasmania has, ow¬ 
ing mainly to the efforts of the Field 
Naturalists’ Club, been scientifically 
well explored, and the following list 
shows the localities of the various 
camps and the depths in which dredging 
has been carried on : — 
1909. —Wineglass Bay, 5-35 fathoms. 
1910. —Cole’s Bay, 10-15 fathoms, 100 
fathoms. 
1912. —Maria Island, 10-20 fathoms, 
1.00 fathoms. 
1913. —Safety Cove, 5-20 fathoms, 60 
fathoms. 
1914. —Wineglass Bay, 5-20 fathoms, 
65 fathoms. 
1915. —Maria Island, 5-20 fathoms. 
Such a list is one of which any club 
might, be proud, and. in conjunction 
with the other work carried out, should 
in a short time make it possible for a 
comprehensive survey of the Tasmanian 
marine fauna to be carried out. 
As regards the Easter trip of 1915, 
dredging was carried out under ideal 
weather conditions. The apparatus 
consisted of a small dredge (intended 
only for a stand-by, and not used on 
the trip), and a 10ft. trawl specially 
purchased by the trustees of the Tas¬ 
manian Museum. The use of such a 
trawl in a boat like the Warrentinna 
is not unattended with difficulty, and 
Captain Kerr is to be congratulated 
on his excellent handling of the boat 
and his good humour through all the 
necessary dislocation of the ship’s rout¬ 
ine which follow's use of dredging ma¬ 
terial. 
The area covered by dredging was 
an extensive one, between Maria Island 
and the mainland, in depths varying 
from five to twenty fathoms. The sea 
bottom here is covered by a carpet of 
the most gorgeously lined sponges, 
amongst which grow masses of sea¬ 
weed. It is, perhaps, not advisable to 
go into details of the “catcher/* but it 
may he mentioned that they included 
almost every form of marine life, poly¬ 
gon, hydrozoa, worms, starfishes, and 
other eehinoderms, Crustacea, mollusca, 
etc., besides fish of various kinds, in¬ 
cluding torpedo (electric) rays, sole, 
flathead, “pipe” fish, and others. 
During dredging operations the sur¬ 
face net was handled to great advan¬ 
tage by Mr. Dechaineux, and the re¬ 
sult showed that the sea here abounds 
iu the small Crustacea (Copepoda), 
pointed out by Professor Herdman and 
others as being of so much importance 
