How to tell male from female yellow catfish? A few practical methods

Yellow catfish, commonly known as geyayu, is a fish native to this area. It is a widely distributed bottom-dwelling fish, and its reproduction rate and yield in Nansi Lake are second only to crucian carp in catch volume.

The yellow catfish has a yellowish-brown body, with a large hard spine on the back and tail respectively, a large head and a wide mouth. It grows rather slowly; in the 1950s the largest individuals reached more than 200 grams, close to half a jin. After the 1980s, because of excessive catching, its body weight gradually decreased; common individuals are about 15 cm long and weigh around 80 grams, while female yellow catfish are one third smaller than males. This fish has relatively strong reproductive capacity in Nansi Lake. Generally, two-year-old adult fish can lay about 8,000 eggs at one time during the peak spawning period from late May to mid-June each year. Its fertilization and spawning can continue from May to September; apart from the peak period, it generally lays about 2,000 eggs. They dig nests to spawn on the bottom of the lake near the shore where there is abundant aquatic grass, and the fertilized eggs stick to the aquatic grass. The parent fish have a very strong ability to protect the eggs and the young, so the survival rate is quite high. As for the feeding habits of the yellow catfish, its main food is shrimp and insects, followed by higher aquatic plants and a small amount of mollusks. Shrimp resources in Weishan Nansi Lake are relatively abundant, providing good conditions for the yellow catfish; therefore, the reproduction rate and fishery yield of this fish are second only to crucian carp.