As we approach the end of July, supermarkets nationwide are beginning to stock up on one of the nation's much-loved summer fish: freshwater eel.

In recent years, however, the cost of eel has risen sharply and consumers are now facing the upcoming Doyo no Ushi no Hi (Day of the Ox, a day dedicated to eel consumption) on July 30 in the knowledge that they'll be expected to pay through the nose for a slab of the freshwater fish.

Rampant overfishing and the scientific community's overall lack of knowledge on the biology of eel has left the industry in a crisis. The dwindling domestic eel population has consequently pushed up prices and forced a number of specialist eel restaurants to close. So scarce is the fish in restaurants these days that it's almost considered to be something of a luxury item.