In Japan, people eat more than one hundred thousand tons of eel per year. In the last 30 years, overfishing has caused the wild eel population to decline by 90 percent.
From The New Yorker:
At Tsukiji, wholesale prices for farm-raised unagi imported from China immediately surged to a record high of around forty U.S. dollars per kilogram, and remained there for much of 2013. Prices for the wild-caught, "natural Japanese" eels served at upscale restaurants like Nodaiwa climbed even higher, by as much as fifty or sixty per cent.
But the government had been late to recognize the extent of the problem, which had already taken a toll on many famous restaurants specializing in kabayaki, a signature unagi preparation. In March, 2012, a year before the species was declared endangered, the beloved unagi restaurant Suekawa closed its doors, after sixty-five years of business, and it was followed a month later by the popular restaurant Yoshikawa.