Lake Ogawara Brackish Water Clam / Ogawarako san Yamato Shijimi

Lake Ogawara Brackish Water Clams are a variety of clam known as Yamato shijimi ⁽¹⁾, raised and caught from Lake Ogawara ⁽²⁾. Its main characteristic is the large size. Since Lake Ogawara Brackish Water Clams are caught after fully raised in about 4 years in the lake, they develop a long shell length that produces a richly-flavored broth (dashi), as well as firm tasty flesh.

Producers at Lake Ogawara use a tool called a joren, which is a special type of scoop, to catch the clams. The only power source that they use to draw their scoops is manpower and the winches on their fishing boats.
　Moreover, the shipping standard for clams only allows clams above the size of 15mm to be shipped to market. Clams not meeting the standard are returned to the lake.
　After carefully removing dead clams following visual and audio inspections, harvested clams are sent solely to the Lake Ogawara Regional Wholesale Fish Market.

The Lake Ogawara has adequate water and bottom sediment conditions that are suitable for the habitat of Yamato Shijimi, which lives in brackish water lakes. Particularly, these conditions include the sodium and dissolved oxygen concentrations of Lake Ogawara, together with its sandy substratum. This makes it one of the leading sites for fresh water clam production in Japan.
　Local fishermen have created a sustainable system for raising and catching fresh water clams since 1983, when they introduced restrictions on allowable catch sizes, etc.
　In 1993, the Lake Ogawara Regional Wholesale Fish Market was opened, making it possible to ship clams caught in the lake to a single distribution point and established a system to ship clams that are stable and high quality.
　The recent amount of the production (catch) remained 1,217 tons (2013), 1,169 tons (2014) and 1,283 tons (2015).

1. Yamato shijimi is a species of edible bivalve that thrives in brackish waters and is endemic to Japan.
2. Lake Ogawara is the largest lake in Aomori Prefecture and the eleventh largest lake in Japan. It is a brackish lake as the salt water enters there with the tidal flow through the Takase River, which is connected to the Pacific Ocean and the Lake Ogawara. Additionally, the lake is the fifth largest brackish lake in Japan and the largest in the Tohoku region.