The portrait and skeleton of this pike was shown for a long time in German museums. Although to this day in popular and educational literature mention pike, supposedly lived 267 years and reached the weight of nine pounds. Thanks to modern methods for determining the age of fish, many misconceptions about the extraordinary longevity of carp, pike and catfish have been dispelled. In this case, the necessary analysis can be done on the gill cover, transverse cutting of the vertebra and auditory stones. How to determine the age of fish that have no scales or is it very small? As a result, fish scale is a true passport for a knowledgeable ichthyologist, which gives the opportunity to find out the age, annual sizes, time spent in the sea, river and number of spawns. On the surface of the scales may remain traces of fish participation in spawning and past diseases.
This means that the young fish went out into the sea from the river, where there was much less feed. Inner year rings are located very close to each other. If, for example, we consider salmon scales, it is easy to see that the fish grew very slowly during the first two years of life. Consequently, at the age of one year, the fish was 60 centimeters long. The distance from the first annual ring to the center of the scale is 6 millimeters. Suppose a meter fish scales with a radius of one centimeter. How to determine the size of the fish in different years of its life?Īccording to scales, you can determine not only the age of the fish, but also the length it reaches annually. Therefore, the answer to the question "How to determine the age of river fish and the age of marine fish?" the same - the habitat does not affect this. It is curious that these annual rings are also formed on the scales of fish in equatorial waters, as well as in fish living at great depths, although it would seem that they constantly live in unchanging climatic conditions. Each of the rings corresponds to 1 year of fish life and is called "winter", although in some cases it may appear in spring or summer. If we look at fish scales under a microscope or even under the most ordinary magnifying glass with a tenfold magnification, then we can easily see rings similar to the rings on a wood saw.
The question "How to determine the age of the fish?" scientists have long been interested in and, as it turned out, this is not so difficult.
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