Sea cucumbers are distributed in Penglai sea area at the junction of the Yellow Sea and Bohai Sea in China, Liaoning, Shandong and Hebei coastal areas, and are mainly produced in Qingdao, Dalian, Changshan Island, Weihai and Yantai. The fishing period is from 1 1 month to June of the following year, especially in June and1February, with the largest catch of sea cucumbers from July to September. The best wild sea cucumber in China comes from the sea area of Zhangzidao, Dalian, 39 degrees north latitude, where the temperature, water depth and salinity are most suitable for the growth of sea cucumber. Moreover, it is far from land, the sea water is pure and pollution-free, and the growth period of sea cucumber is long. Therefore, the wild sea cucumber produced has the highest meat quality, wall thickness and nutritional value. It is the best kind of sea cucumber and is known as the "crown of ginseng". However, because it is wild, the sea area is small and the yield is very high. But the same quality of sea cucumber, Tongrentang is more than twice that of Fulinmen.