Tuna Farms //

Mixed Concerns & Hope for Tuna
In February of 2009 off the coast of Italy researchers injected Bluefin Tuna with hormones in order to stimulate spawning in captivity for the first time. Previously Tuna farms were of no real benefit since they had to be continually repopulated with wild Tuna. The stationary lifestyle of the farm caused a drop in a particular hormone necessary for spawning with the product being that until now Tuna farms were little more than Tuna holding pens.

There are mixed concerns regarding the success of this endeavor. One being, that as Tuna farms become more profitable and as such, more plentiful, will they have similar adverse effects on the species and the environment that salmon farms have had. It is well known that when you house a large population of fish together in close quarters that parasites and disease run rampant. Another concern is that the fecal waste of a large volume of stationary fish will harm the sea floor below and change the ph of the water in that area, again creating a breeding ground for disease and parasites that may harm wild fish of numerous species in nearby waters. Because Tuna farming is still relatively new, it remains to be seen whether they will suffer these same ill effects. Another concerning question scientists are asking is how does the stationary lifestyle affect how healthy the Tuna is as a food source.

With these concerns though, there is also hope. Hope that young tunas from farmed stocks can help to supplement the dwindling numbers of wild Bluefins. These hopes have become even more vital and important in recent days after the proposal for the ban of bluefin tuna exports at the Convention on International Trade in Endangered Species was squashed. There has also been some promising research showing that farmed Tuna’s mercury levels are significantly lower than that of wild stocks. So even though people are still decimating the Bluefin populations there may be a possible solution on the horizon. At the very least a band-aid.

References:
http://www.physorg.com/news179255911.html
http://www.mnn.com/earth-matters/wilderness-resources/stories/farm-raised-bluefin-tuna-spawn-controversy#

http://costaricanconservationnetwork.wordpress.com/2009/10/21/follow-me-on-the-no-tuna-farm-trail/

Comments

  1. a true closed life cycle tuna farm that takes brood stock, hatches larvae from eggs and then grows them into full sized adults, hasn’t happened yet. Why? A small tuna or “fingerling” develops its tail fin before its pectoral fins. This allows the tuna to go from something like 0-60 mph in the blink of an eye to escape predators. In the open ocean it doesn’t have to “steer” with its pectoral fins because there is nothing in its way to “steer” around. But put a fingerling in a tank, have the sun go behind a cloud, and the fish gets spooked, takes off, and WHAM, bashing itself right into the side of the take, killing it. This is called "walling". Scientists are getting good at raising fingerlings, but they’re still having trouble keeping them alive, so much so that it’s still not economically viable to raise tuna like this. That’s why folks go out with their nets...and, well, you know the rest.

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