Tandanus tandanus (Mitchell
1838)
|
his months factsheet (July 2000)
concerns a group of fish that I thought that I would not be featuring
on ScotCat, but such is the interest in the U.K. for Australian
catfish now that I decided to include the Australasian continent
on my homepage catfish map, and on my research on Tandanus
tandanus, the 'Eel-tailed Catfish', I found this to be
a very interesting fish and indeed has wet my appetite to try
one day to go 'down under' and sample the delights of trying to
catch them.
As mentioned earlier Australian catfish
have started to appear in some aquatic outlets in the U.K.which
has led to further interest. There is not an abundance of freshwater
catfish species in Australia-New Guinea akin to the South American
and African/Asian continents, there is as far as I know only
about 16 species.
Tandanus tandanus is actually the largest catfish compared
to the smaller Neosilurus species and as such is prized
as a good food fish and to be one of the best flavoured fish
for the home plate. It is said that it is easily caught on baits
of shrimps and worms and 'camp' leftovers. One word of warning
with these fish, as with most cats of the Plotisidae
family, is their very sharp dorsal and pectoral spines and I
have included the following extract from an Australian fisherman
Barrie Gill on this subject.
"Catfish can be a bit of a handful
once landed, and one should be particularly careful of the spikes
in the dorsal and pectoral fins. These spikes are extremely
sharp, and if you are spiked it will cause intense pain that
will last for hours. I once walked on one while walking along
a dam shoreline. The spike went straight through my boot,
and I was in a lot of pain for a couple of hours. The pain only
stopped when I got myself to a hospital and they gave me an
injection. I have had friends call me a big baby when I tell
them this story, but I don't care, all I can say is that a catfish
has never spiked them. So please be very, very careful when
handling catfish, and never just place them in the bottom of
a boat. That is only asking for trouble, and if you step on
one you will know what trouble is."
If you do come across some Australian
catfishes and fancy giving them a go I have included a couple
of line drawings to help differentiate between the Neosilurus
and Tandanus species, notice the difference in the caudal
and anal fins where Tandanus has an uninterupted anal
fin which is connected to the caudal and ends just posterier
to the dorsal, whereas Neosilurus stops well short of
the dorsal fin. Both species sport 4 pairs of barbels which
they tend to hold out erect.
Acknowledgments: Nick Thorne, Webmaster of Native Fish
Australia for his interest and help. Barrie Gill for his
help on this factsheet.
Head broad, somewhat flatened; body tapering
posteriorly; a small dorsal fin anteriorly, composed of a sharp
spine and 6 or fewer soft rays; second dorsal and anal fins confluent
with caudal fin, containing about 150 rays; pectoral fin with
sharp spine and 10 soft rays; caudodorsal fin base about 50% of
Standard Length, originating on middle of back; gill rakers on
first arch 23 to 32.
Colouration tends to vear from a mottled
reddish-brown on the back and sides, with the underside white/yellow,
to a mottled olive-green. The nasal barbels (on top of its snout)
vary in colour uniformly with the body, in the former being pink,
in the latter pale green. The colouration is influenced to a large
extent by its surroundings.
Well if we are not going to fish for Tandanus
tandanus for food puposes but, as I am, more interested in
them as a addition to an aquarium it may come as a surprise that
for such a large fish (90cm) they are quite suited for an aquarium
as juveniles and can become quite tame in captivity. I would of
course not house them with small fish and you would be looking
for a larger tank of 4ft and above to accommodate them. The size
of 90cm is of course the size they grow to in their natural habitat
and they will grow only to about half (45cm) this size in an aquarium,
so housing them with larger Characins and or Cichlids could work
but I would be more inclined to house even a pair of them by themselves.
They are not overly territorial but I would include some retreats
for them with safely constructured rockwork. These fish are great
escape artists so make sure you have a properly constructed lid
for your tank.
The male builds a large nest out of sandy-grit
or pebbles where he entices the female to spawn. After spawning
the male guards the nest for up to 2 weeks and they can lay up
to a grand total of 20,000 eggs. They hatch after 7 days at a
temperature of between 19-25c (65-77f). Sexing out this species
is easy with the male possessing a long cylindrical papilla and
the female a triangular urinogenital papilla.
In its native habitat they feed on insect
larvae, prawns, crayfish, molluscs and small fish. In the aquarium
they will eat anything given such as earthworms, chopped liver,
frozen brine shrimp, prawns, pellets and flake.
| Etymology |
| Tandanus:
A local name, tandan, in Australia |
| Glossary
of Terms: |
Gill
rakers : Structure
on the upper portion of the gill arches.
|
| Reference |
Native
Fish Australia
Allen, R.Gerald.
Freshwater Fishes of Australia.1989.
Roughley, T.C. Fishes of Australia and their Technology
1916.
Burgess, E.Warren Dr. Atlas of Freshwater &
Marine Catfishes 1989. |
| Photo
Credits |
Top Picture: Barrie
Gill
Middle Colourplate: Chas.Thoms.
Bottom Linedrawings: John R. Quinn. |