1. Among these four kinds of perch, Songjiang perch is the best, which is produced in Wusong River basin. Songjiang four-gill perch is the most popular perch because it is fresh and tender. However, Songjiang four-gill bass is a national second-class protected animal and is not suitable for eating.

2. The largemouth bass, native to the United States, is a freshwater fish. Most of the freshwater bass seen in the market are of this kind, with a yellow-green body surface and a dark green back. Its identification mark is a black stripe in the middle of both sides of the body, extending from the head to the caudal fin.

3. Perch, a kind of biological perch. In China, perch only exists in Xinjiang. Because there are five black vertical stripes on both sides of its body, it is commonly known as five black stripes.

4. Songjiang perch is a migratory fish, which belongs to the national second-class wild protected animals.

5. Sea bass are distributed in the coastal areas of China, and they like to live in estuaries.