Hokkigai, commonly known in English as the surf clam, is one of Hokkaido’s well-known shellfish. Its official Japanese name is Ubagai, but throughout Hokkaido it is widely called Hokkigai, or “Northern clam.” It is found in sandy coastal waters across much of Hokkaido.
Hokkigai has a distinctive shape, roughly oval with a slightly triangular appearance, and is a thick, heavy bivalve. Adult clams generally live buried about 15 to 30 centimeters beneath the seabed. They move closer to the surface in summer and deeper into the sand during winter.
When served raw, Hokkigai has a firm, satisfying texture and a fresh marine flavor. This makes it especially popular as sashimi or as a topping for sushi. Most Hokkaido Hokkigai is shipped live and still in its shell, helping preserve its freshness.
Hokkigai is not limited to raw preparations. Boiling brings out a greater natural sweetness, while the shellfish can also be enjoyed in a variety of other dishes.
Popular preparations include fried Hokkigai, butter-grilled Hokkigai and vinegared dishes. Its firm texture allows it to remain pleasantly substantial when cooked, while its natural sweetness becomes more pronounced.
Because Hokkigai thrives in the sandy coastal waters surrounding Hokkaido, it has become an important part of the region’s seafood culture. Its combination of freshness, marine flavor and satisfying bite makes it a favorite among both local diners and visitors.
The peak season for Hokkaido Hokkigai is June through August. Visiting during these summer months offers an excellent opportunity to enjoy this distinctive shellfish at its seasonal best, whether as sashimi, sushi or a cooked dish.