Efforts to save Bluefin tuna face challenges




Bluefin tuna has proven to be a very popular fish in many aspects of the fishing industry. It’s popularity has proven to be a danger to its species as it closes to its final fate of extinction. Many fishing countries around the world can benefit from the profits in fishing this species. Having its extinction coming closer and closer some efforts have been made to farm-breed these fish, the effort has not been without some setbacks and surprises. These efforts have proven to be successful to a point at a very slow pace, yet fruitful outcomes give hope for the future.
Yoshifumi Sawada is a biologist in Japan’s Kinki University, he comments the bluefin’s eccentric habits have made them easy prey for fishers. As the demand for their meat in sushi and sashimi has risen so has the frequency of fishing for young bluefins. Due to the origin of these traditional dishes Japan initiated a program in the 1970’s to farm-breed the bluefin tuna. Early studies and trials seemed to be fruitless due to the bluefin’s size and eating habits. The bluefin tuna is considered to be one of the ocean’s largest predators. Before overfishing took place, their normal size and weight was 4 meters long and weighing half a ton. Bluefin tuna is also an animal similar to sharks, where they must move continuously to force water over their gills. This also proved to be an issue as this required much larger tanks than the usual fish-farming species. It took a group of biologists form Kinday, a part of the Kinki University, 4 years to learn how to maintain the bluefin tuna in a relatively large enclosed space without having them suffer from the lack of space.
All of these efforts also take their toll in the pocketbooks of universities and conservationist teams. The estimated annual budget of the Kindai group added to be about 25$ million. This gave some urgency to the success of the program. After much persistence in 1995 the program was able to spawn six fish that survived through adulthood. This meant that the bluefin’s lifecycle was completed and farm-breeding this species was becoming a reality. Their goal now is to be able to raise the tuna from eggs and release once reached maturity. According to the Kindai group, there still needs to be many issues resolved before they can start releasing tuna into the wild and impact natural populations.

To learn more about the Kindai group and their work visit:

http://ccpc01.cc.kindai.ac.jp/english/e_r/Fish.htm

To learn more about bluefin tuna go to:

http://marinebio.org/species.asp?id=236

-Gonzalo Romero

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