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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 collect them.

Tandanus tandanus

 

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."

 

Tandanus tandanus - colour plate (1916)

 

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.

 

Tandanus

 

Neosilurus

 

 

Acknowledgments: Nick Thorne, Webmaster of Native Fish Australia for his interest and help.  Barrie Gill and Louissa Rogers for extra information on this factsheet.

Update April 2013: Tandanus tandanus are now protected in South Australia and Victoria and NSW fisheries has recognised the Murray-Darling Basin population to be endangered in Victoria according to DSE’s Advisory list of Threatened Vertebrate Fauna in Victoria - 2003 (DSE 2003) under the Flora and Fauna Guarantee Act 1988 (FFG Act).

Eel-tailed Catfish, Jewfish, Tandon

Plotosus tandanus

-

Australia: In the Murray-Darling basin in North Western Victoria and Western New South Wales.

90.0cm (36ins)

15-30°C (57-87°F)

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 their natural habitats they require specific temperatures for spawning, and so alterations to temperature regimes in rivers and streams may threaten the species’ breeding activity. Siltation of waterways, as a result of clearing and poor land management practices, may also affect spawning success.

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.

Gill rakers: Structure on the upper portion of the gill arches.

Tandanus: A local name, tandan, in Australia.

Allen, R.Gerald. Freshwater Fishes of Australia.1989.
Burgess, E.Warren Dr. Atlas of Freshwater & Marine Catfishes 1989.
Department of Sustainability and Environment: Action Statement, Flora and Fauna Guarantee Act 1988. No. 201.
Gill, Barrie. pers comm. July 2000.
Native Fish Australia
Rogers, Louissa; pers comm. April 2013.
Roughley, T.C. Fishes of Australia and their Technology 1916.

Photo Credits

Top image: © Barrie Gill     
Middle Colourplate: Chas.Thoms.
Bottom Line drawings: John R. Quinn.