Lake Togo Shijimi (freshwater clam) is known for its large size and exceptional flavor, making it a unique specialty of this brackish lake. Particularly, the Lake Togo Shijimi is referred to as "black diamonds" due to its size and beautiful sheen. Fresh clams possess a delightful, firm texture, and when frozen, their umami flavor is reported to increase by up to eight times compared to fresh clams. The peak seasons for these clams occur in summer, just before spawning, known as "Doyo shijimi," and in winter, when they grow in cold water, referred to as "Kan shijimi (cold shijimi)."