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    BLUEFIN TUNA OVERFISHING

    The world has a huge appetite for tuna, and tuna are among the most valuable fish in the ocean. In order to meet demand -- and turn huge profits -- various species of tuna have been overfished to critical levels. In particular, bluefin tuna, the largest of all tuna species, are nearing extinction due to overfishing. Just last week, a report showed that overfishing has pushed the stock of the Pacific bluefin down by 96.4 percent. Stocks can recover, but it will take tighter regulations and stricter enforcement of existing laws regarding how these tuna are fished. (Discovery)