Offshore Surface 415 Sea of Japan, Tsushima Current waters

Basic Information References

Reason(s) for selection Criteria

Characteristics References

In these waters the Tsushima Current flows north, mixing with the Kuroshio Current, waters of the East China Sea from coastal China, and others. The Tsushima warm current is a surface current with warm, high-salinity, low nutrient water, but at the complex front area with the Liman Current, highly productive primary production similar to that of the Oyashio-Kuroshio transition region occurs. Warm-water fish whose main spawning grounds are in the East China Sea (Pacific bluefin tuna, yellowtail, saurel, and others) and Japanese flying squid migrate north along the Tsushima Current, and starting in the fall, they migrate south toward their spawning grounds from the San-in Coast to the East China Sea. On the continental shelf and slope areas, warm-water species are numerous toward the south and cold-water species are abundant toward the north. A large number of snow crabs inhabit the baythal zone. Dominant fish here include Maurolicus japonicus, Bothrocara hollandi and others. In addition, firefly squid and others are distributed in waters roughly 200 m deep off the coast from Hyogo Prefecture through Shimane Prefecture, which are important spawning grounds for these species. Due to its steep terrain, Toyama Bay sees upwelling currents from the sea floor, and since it also includes an abundance of riverbed water from the land, rich nutrients are transported to the surface layer. Another characteristic of these waters is their large volumes of phytoplankton and zooplankton growth (Sakurai, personal communication). Toyama Bay are also famous for their large production of firefly squid (Nakata, personal communication).