It’s been lost under the sea for eighty five years – but now it’s been found.
A chance catch by a South Australian fisherman has confirmed that a species of fish first identified 85 years ago – but not seen by scientists since – has been rediscovered in the Great Australian Bight.
CSIRO marine scientists have identified the ‘lost’ species as a giant roughy or giant sawbelly (Hoplostethus gigas), first recorded in 1914 after a fisheries survey in the Bight by fisheries scientist, Dr Harald Dannevig.
"This is good news about a species that hasn’t been seen in a long time" said Dr Peter Last.
Dr Last, a taxonomist, who is co-authoring a CSIRO identification guide for edible Australian fish species – the Australian Seafood Handbook which will be published later this year.
Funded by the Fisheries Research and Development Corporation and CSIRO, the Australian Seafood Handbook will be published later this year.
Dr Last had been in Port Adelaide photographing and recording commercial species coming off Great Australian Bight trawlers, and had been speaking with fishermen, industry managers and processors about species on the Handbook ‘wanted’ list.
At the same time, Port Adelaide trawlerman Tim Parsons and skipper of the Noble Pearl, a Raptis and Sons vessel, had been sorting his catch and had put aside a selection of fish including the giant roughy and the similar Darwins roughy, distinct because of their pink bodies.
"Several roughy species are caught from time to time off southern Australia. So given the substantial survey and commercial fishing effort in the last few decades, the absence of this species in catches had remained a mystery," Dr Last said.
"That day I’d given Raptis Vessel Manager Craig McDowall Dannevig’s description of the fish, then minutes later he called me over and said: ‘How about these?’
"There they were – the fish Dannevig had discovered some 84 years earlier", Dr Last said.
At the time of the original finding, Dr Dannevig was Commonwealth Director of Fisheries and subsequently was referred to as the father of Australian fisheries research. Dannevig gave the specimens to an ichthyologist, McCulloch, who made a full recording of the species including an illustration. The same year Dannevig and 20 others aboard Australia’s first fisheries research vessel, the 335 ton steamer Endeavour, lost their lives in a gale while returning from a voyage to Macquarie Island.
Dr Last said the finding by Tim Parsons was important because it confirmed that this roughy still existed but probably has a very restricted distribution. The fish had been caught in a trawl in water between 180 metres and 350 metres deep in the same general location as Dannevig’s 1914 trawl.
Dr Last said that because no other giant roughys had been located until last year’s landing, it is likely the species is one of a small suite of animals found in the deep central part of the Great Australian Bight which is lightly fished or not fished at all. It is also likely to live on or close to ‘rough’ bottom where it has avoided trawling.
He said scientists – working closely with commercial fishermen – were strategically sampling the deep oceans and coasts to build the profile of Australia’s marine biodiversity.
"In the past 30 years scientists have identified an additional 2,000 species of Australian fish," he said.
Dr Last said the reasons for such diversity could be traced in part to the ancient separation of the continents and water temperatures with species being isolated off the evolving Australian east, west and south coasts.
"That ultimately left some species confined to the Great Australian Bight and this giant roughy is one of them," he said.