Breeding Tuna ‘Like Cattle’ A Step Closerff

Australian aquaculture pioneer Clean Seas Tuna Limited has successfully induced reproductive maturation among male Southern Bluefin Tuna (SBT) broodstock housed in the company’s purpose-built, land-based breeding facility at Arno Bay. The company says it expects to duplicate Australia’s 5,200 ton Southern Bluefin Tuna quota in a decade.

It is the first time in the world that reproductive maturation of SBT has been achieved under controlled conditions and is a major step towards achieving the company’s long-term goal of breeding and growing out SBT from its own broodstock with the goal of duplicating SBT wild catch, which is currently subject to a strict international quota system.

Clean Seas Chairman, Hagen Stehr AO said the world-first breakthrough was achieved using hormonal therapy developed in Europe to mimic the natural production of hormones by wild fish and carried out in Clean Seas’ Arno Bay breeding facility which was developed with the funding assistance of a Federal Government Commercial Ready Grant.

He said the breeding breakthrough was undertaken with the cooperation and supervision of internationally acclaimed tuna scientists, Professor Christopher Bridges of the University of Dusseldorf and Dr. Constantinos Mylonas of the Hellenic Centre for Marine Research. 

The courtship behavior and release of sperm by the captive SBT was documented using underwater video observations.  The broodstock will continue to be monitored and the therapy potentially repeated, with the expectation of completing their reproductive maturation and producing viable (fertilized) eggs.

“This is a major breakthrough in our quest to close the lifecycle of Southern Bluefin Tuna as we have replicated in our land-based breeding facility the complex and previously unknown natural breeding conditions of one of the wildest fish in the sea – the first time in the world that has been achieved, and only three months after commissioning the facility and moving our fish from the ocean,” Mr. Stehr said.

“While we still have some way to go to reach our ultimate goal, we have made giant strides over the past week.  The next step will be to stimulate the natural release of eggs from our female broodstock and their subsequent fertilization, at which point we will be in a position to return domestically-bred SBT fingerlings to our pens in the pristine waters of Arno Bay where they can be grown to order for the restaurants of the world.

“Ultimately, this will be the equivalent of domesticating and breeding cattle for food – but on a new frontier,” Mr. Stehr said.

“Fish will increasingly provide the world’s growing need for protein and economically and environmentally sustainable aquaculture programs such as ours are the key to delivering the world’s fish requirements.”

Mr. Stehr said Clean Seas had the potential to duplicate Australia’s 5,200 ton Southern Bluefin Tuna quota in a decade, without impacting on wild tuna stocks.

Clean Seas Tuna Limited listed on the Australian Stock Exchange in December, 2005.

Clean Seas’ major shareholder, the Stehr Group was established in the early 1970s and is now recognized as an Australian leader and international pioneer in tuna fishing and offshore fish farming. In 2004-05, the Group produced more than 650 tons of farmed SBT, more than 600 tons of aquaculture-bred Yellowtail Kingfish and in excess of 200 tons of aquaculture-bred Mulloway.