What structures of the perch can be used to determine its age.

The age of a perch, like that of other fish, can be determined using a conventional magnifying glass. You just need to take the scales and examine it carefully. With every year of life, annual rings are formed on the scales of the fish, which will not only tell about the age, but also the living conditions, spawning, and diseases of the inhabitant. Also, the age of the perch can be determined by examining the bones: vertebrae, gill covers, flat bones of the skull. To do this, the bones must be treated with gasoline or ammonia and cut. Next, consider the annual rings, as well as on the scales.