If you enjoy your sushi fresh, you won't have to worry about it running out any time soon. Scientists from the Tokyo University of Marine Science and Technology have been studying for a way to preserve the dwindling fish population due to overfishing and may have found just the solution to stem the tide.

By injecting specialized trout sex cells into salmon embryos, scientists were able to produce male salmon that can inject trout milt (semen), as well as female salmon that can bear trout eggs. One out of four salmon offsprings have been found to have coloration and traits similar to the target trout species they have been trying to preserve. Furthermore, these trout offspring were able to produce more of their corresponding species through normal fertilization means.

Other endangered fish species have also been targetted, such as the brown trout and the Japanese char. However, their real goal is the repopulation of Japan's favorite fish: the bluefin tuna. There have always been difficulties trying to breed such a species in captivity, but with this method Goro Yoshizaki, a marine bioscientist, explains the benefits that such a method will have on the fishing industry: "If we can produce surrogate mackerel, whose body size is 500 to 1,000 grams—nearly 1,000 times smaller than tuna—we can save space, cost and labor to produce a tuna baby."