How to learn the age of fish in simple ways?

If you are fond of biology, you probably know how to determine the age of some species of animals and plants. So, in cattle age can be recognized by the horns: each lived year leaves the ring. In a similar way, you can find out the age of the tree. Having looked at the number of annual rings on his saw, you can, within a couple of years, find out how many years ago it grew. But how do you know the age of a fish? This is especially interesting for fishermen, who occasionally catch spectacular specimens.

Well, it's not that hard. But first it is necessary to refresh in memory some biological aspects concerning these inhabitants of fresh and sea waters. Their body is covered with scales, which protects the fish from mechanical damage and parasites, and also serves as a "fairing", which improves the hydrodynamic parameters of the fish, allowing it to move in the water column at a higher rate. So, scales - this is a kind of analogue of a tree. Asked how to know the age of a fish, you need to tear off one scaly and look at it carefully.

The fact is that on the scales the same annual rings are formed, which can be seen on the spits of trees or horns of cows. By the width of the ring you can find out about what the year was, if there was enough food for the fish. The wider the ring, the more favorable conditions were at that time. However, before you know the age of a fish, it is worth knowing what scales to take. Scales from the middle part of the lateral line are ideal. Before determining the age, it should be dried properly and counted under the magnifying glass.

However, how do you know the age of a river fish that has no scales on its body? These include burbot and sterlet. In addition, in such species as the ruff, perch, or pike, the scales are so small that they can be examined only under a microscope, and in this case it is no surprise to make a mistake. To solve such a problem it is necessary to resort to the help of another method.

So, perch for determining the age is used dried gill cover, for vertebrae years are considered ruff or burbot. In a noble white fish, age can be determined from the spicules of the rays of the anterior vertebrae, and they must also be dried properly beforehand. But how do you know the age of a fish in this case? It's simple: the above parts of the body after drying, you need to saw, and on the cut will be clearly visible all the same year rings, which you need to navigate, determining the age of the fish.

Do not assume that the methods described by us are good only for freshwater fish. They are also suitable for marine fauna, which often does not have scales or is too small. Those who are thinking about how to know the age of marine fish, remember that to count its annual rings may take a long time. So, a few years ago near Alaska a grouper was caught , the age of which was estimated by biologists as much as 200 years!

However, according to a number of researchers, until recently, catfishes of even more respectable age could be caught in our rivers. Some scientists believe that a number of deep-sea fish live almost forever, dying only from the action of elements or attacks of predators.