An increase in the sterlet population has been recorded in the Dnieper

During one of his recent dives in the Dnieper, free diver Alexander Gromadsky discovered a fish that was surprisingly similar to a sturgeon at the bottom of the river, within the city limits of Dnepropetrovsk, writes gorod.dp.ua. The fish, 40-50 centimeters in size, dozing on the sandy bottom turned out to be quite active and quickly swam away from the curious diver. Alexander managed to film it with an underwater video camera and examine a fairly large, but not fatal wound on the side of the fish. “Divers and fishermen know that sturgeon family fish have long been found in the Dnieper,” says Vadim Manyuk, PhD in Biology and associate professor at the Oles Honchar Dnipropetrovsk National University. “And the population of the only sturgeon family species in the Dnieper, the sterlet, has survived to this day. But there are very few of these fish, they lead a solitary life, although they are occasionally caught in fishermen’s nets. And although the ecological situation in the Dnieper does not contribute to the prosperity of this species, a small increase in the sterlet population has been recorded in recent years. Judging by the video, it was a young sterlet that caught the diver's eye.

A professional ichthyologist, professor of the Department of Aquatic Bioresources and Aquaculture of the Dnepropetrovsk State Agrarian and Economic University Roman Novitsky also believes that it is a sterlet in the video fragment.

- Before the construction of the cascade of dams on the Dnieper, there were five species of sturgeon in our river! - he says. - Now, of these native species, only the sterlet remains, listed in the Red Book of Ukraine. Several times a year, it is caught by fishermen fishing with a bottom fishing rod or one of the favorite delicacies of this fish - boiled corn. Attempts to return sturgeon to the Dnieper have been made more than once. Sturgeon juveniles were released two years ago and a year ago. Perhaps some of the fry from these stocking attempts survived. But judging by the video fragment, the diver saw a young sterlet.

It is very difficult for a non-specialist to distinguish a sterlet from a sturgeon. As ichthyologists explained to us, the differences are most noticeable if you compare adult specimens. The sterlet is the smallest fish of the sturgeon family. Its length rarely exceeds 125 centimeters, on average it is 60 cm. The sterlet weighs up to 16 kg. But this does not mean that all adult specimens weigh that much, the average is 5-6 kg, and adult fish weighing up to 3 kg are often found. An adult sturgeon is one and a half to two times larger.

Unlike the sturgeon, the sterlet has a narrower head, as well as a long and sharp nose. This small fish of the sturgeon family also has long fringed barbels. Sturgeon also have whiskers, but they are shorter. Sturgeon can be recognized by a large number of lateral scutes (bony shields). It can have up to 70 of them (while sturgeon have about 50). Sharp spines emerge from the shields located on the back of the sterlet.

Sturgeon "fatten up" in the sea before spawning, sterlet is a sedentary fish. Considering our remoteness from the sea and the obstacles on the way to it in the form of dams, the chances of sturgeon overcoming these obstacles, "fatten up" in the sea and returning to us to spawn are minimal. Therefore, the population of fry released into the Dnieper, alas, is practically doomed to gradual extinction.
More details (video): http://dv-gazeta.info/dneprnews/v-dnepre-zafiksirovan-rost-populyatsii-sterlyadi-video.html