Shishamo is a small fish around 13cm in length that like salmon is born in a river and returns to the same river to spawn after it spends two years in the ocean.
Capelin is a fish often substituted for shishamo. Although it belongs to the same osmeridae family of fish, biologically speaking the capelin differs from the shishamo. The way to tell the difference is at first glance the shishamo’s scales are quite defined and the meat features a delicate taste despite being rich in protein.
The shells of the female’s eggs are quite thick, so they don’t easily break when cooking. Generally shishamo is first dried then grilled and eaten, but when eaten raw, it offers a refreshing scent like the sweetfish.
■A rare fish species that only spawns in a limited number of rivers Normally the shishamo spends most of its time in shallower seas at a depth of at least 120 meters along the Pacific Coast. In the autumn the fish forms schools which then return to specific rivers to spawn. The schools off the coast of Hidaka, Kushiro/Tokachi and Akkeshi each differ genetically. Shishamo are caught in an area that extends from Noboribetsu City to Hamanaka Town in the Kushiro area. The total shishamo catch for all of Hokkaido is only 939 tons (*Source: 2012 Fisheries in Hokkaido), making it one of the more rare catches.
■ Map / Main municipalities with fishing grounds
Hiroo Town, Kushiro city, Shiranuka Town, Toyokoro Town, Urahoro Town, Taiki Town, Erimo Town, Mukawa Town, Atsuma Town, Hidaka Town
Shishamo is a fish species unique to Japan and only found along the Pacific Coast of Hokkaido. Most of the shishamo sold at market are capelin, a non-native species of fish that is often substituted for shishamo.
Mukawa Town is widely known as the capital of shishamo. In the past, it is said that the local river appeared black because of the massive school of shishamo swimming upstream. The shishamo population is believed to have decreased gradually due to overfishing and changes in the natural environment caused by disasters.
Today, environmental improvements are being developed to protect shishamo from the impacts of natural disasters and aid in their upstream swim to spawn.
The fishing season begins in autumn when mature shishamo head from the ocean up river to spawn. Fishing takes place between October and November in the Kushiro and Tokachi areas, and October in the Hidaka and Iburi areas. Shishamo are caught in huge quantities using bag nets or by spearfishing, stationary nets, or trawling.