Methane venting victims? 4 kilometres of dead sardines wash up on the coast of Hokkaido, Japan

On 11/3/2014, numerous sardines were found washed ashore in Pacific coastal area of Hokkaido. A fisherman found them around 6AM in the day.

The location was Mukawa-cho in Hokkaido. The dead sardines were approx. 15 ~ 20cm long, which were fully grown. They were found washed ashore for 4km along the coast.

The local fishermen state they have been fishing there for 60 years but haven't seen such a thing.

Hokkaido fisheries experiment station comment it might be due to the storm one night before, but the exact cause is not identified.

On the other hand, local citizen commented on Twitter that that kind of storm was nothing rare, can happen quite often.