How to catch the carp just released in the black pit?

Carp is a common fish in China, which not only tastes good, but also has high nutritional value, so many people like to eat it. At present, this kind of fish can be found in many fish ponds and black pits, and 80% of the carps in the black pits are carp. How to catch the carp that has just been released in the black pit?