The rich, creamy red meat of the bluefin tuna is prized almost to a cultish degree -- at Tokyo's Tsukiji fish market, a single majestic specimen can sell for over $100,000 -- and as a result the species is severely overfished and endangered. Farming the fish, which might offer a solution, has proven remarkably difficult. After years of experimentation with sexy mood lighting, Australia's Clean Seas company only managed to get them to breed in captivity by injecting them with spear guns full of reproductive hormones. Now, a European initiative has announced an alternative.
The Selfdott project reports the first success breeding Atlantic bluefin tuna in floating cages without the use of hormones. True, the hatchlings all died within months, but the fish experts are confident that a change of diet will fix that next time.
Fish farming has the potential to offset the damage done to natural tuna populations by extreme overfishing. The caged fish are even likely to make tastier sashimi than wild ones, since they can be fattened as much as is desired. But it's not a panacea by any means.
Tuna is one of the most environmentally punishing fish to farm, in part because the fish takes a decade or more to mature. During this time, the captive fish are fed massive amounts of smaller wild fish -- an estimated 20 tons of food fish goes into each ton of tuna produced -- so those prey species may become depleted in turn. The farms also produce high concentrations of fish waste, polluting the area around the farm, and can be breeding grounds for piscine diseases and parasites like sea lice.
If only Thunnus thynnus wasn't so delicious.
so farm the tunas food, all that fish waste can be fertilizer for algae which is the beginning of the food chain anyway
Interesting article, but please use some SCIENCE in it..
Fish farms do not pollute the area around them.
seriously. Ask anyone who has owned a goldfish. if you let the bowl get dirty, the fish die. Fish die VERY easily.
If fish farms were polluting the water around them, their stock would die very fast.
Stop listening to Eco-Terrorists like Suzuki and Morton.
all they do is use Junk science. Any real scientist would look at how they do their so called research and laugh.
They use mis-information, information that is decades old, or just outright lie to get their political agenda across.
and yes the diet may be 20 tonnes for 1 tonne of growth - which is a horrible conversion ratio, but take the average salmon - wild is ~7kg feed to 1kg growth, and a farmed salmon is between 1.1 kg to 1.4kg feed to 1kg growth.
the Tuna industry when it starts to gain some momentum, will get better. 20:1 ratio in the wild will not be the same when they get the diet down properly.
Prof.Hilarity. "Fish farms do not pollute the area around them.
seriously. Ask anyone who has owned a goldfish. if you let the bowl get dirty, the fish die. Fish die VERY easily."
Are you serious?? Gold fish bowls don't have water currents flowing through them! The ocean has biological and geologic filters. Concentrating an inordinate amount of fish unnaturally in an area, the effects of their left over food and droppings, swept away by currents, DOES affect the whole system. Over-burdening the natural filters and their limited capacity to clean themselves leads to a build up of unwanted and unnatural conditions in the whole system. That is the logical definition of pollution.
The logic in worrying about what humans do to profit from the natural world around them seems to evade me. You can't stop people. Unless you STOP them. And who is going to do that?
@UFCwarrior: you amaze me every time your post something. Here in Japan we sometimes pay over $100,000 for 1 tuna. OBVIOUSLY cost is not an obstacle. People want their tuna. If it goes extinct they can`t have it AT ALL.
you seriously have no clue what you are talking about.
I have done alot of testing with the government, sediment tests, up and down current to sea sites, to 1km away, and then 5 km from any sea sites.
guess what. there is not much difference. fish do not produce sewage and some crackpots like to say. sewage is a WARM BLOODED animal biproduct. fish from the farms give off inert waste. there is a HUGE amount of life around ocean sites. I have dove quite alot of them.
Are you serious??
> yes I am.
Gold fish bowls don't have water currents flowing through them! The ocean has biological and geologic filters. Concentrating an inordinate amount of fish unnaturally in an area, the effects of their left over food and droppings, swept away by currents, DOES affect the whole system.
> Not really. you obviously do not know much about fish biology. Any food that is not eatten by the fish are eatten by wild fish - or it broken down by micro-organisms that are in turn eatten by other animals and then fish.
Over-burdening the natural filters and their limited capacity to clean themselves leads to a build up of unwanted and unnatural conditions in the whole system. That is the logical definition of pollution
> again, farms are not over burdening any natural systems
go back to school. really man.
Aquaculture in north america is so OVER regulated, in fact, if you tried to impose the amount of regulation and watchdogging to ANY OTHER FOOD INDUSTRY that industry would fail and be shut down so fast it would make your head spin.
and before you go off on the whole anti-biotic thing which is a joke in itself.... take this fun fact. Canadian Pork - just in canada uses more antibiotics in one month than worldwild antibiotic use in aquaculture in ONE YEAR.
get educated before you open your mouth.
there is NO science at all in what the eco terrorists like to spout off like suzuki and alexandria morton.
it's been proven I don't know how many times, that these organizations use mis-information, half-truths, ommission and outright lies to get their political agenda across.
and the media loves it - sensationalism.
aquaculture is a good industry and it's getting cleaner and greener each year. We need this. and we need to keep growing and green.
There are none so blind as those who refuse to see.
stop eating animals!
Podboq, exactly. so open your eyes.
that was the most intelligent thing you have had to say.