Scientists have registered in the middle reaches of the Amur the mass death of salmon going for spawning from the Pacific Ocean to the fresh waters of the taiga river and its tributaries, Boris Voronov, director of the Khabarovsk Institute of Water and Environmental Problems, Corresponding Member of the Russian Academy of Sciences, told RIA Novosti on Tuesday
According to him, scientists, specialists of the Ministry of Emergency Situations and employees of the prosecutor's office are currently looking for the reasons for the mass death of salmon.
Salmon mor is a problem for the inhabitants of coastal villages. There is a smell of decaying carcasses in the air around the clock. As directed by local authorities, dead fish are harvested daily, but the number of dead red fish continues to rise.
A similar case of mass death of chum salmon in the Amur was noted in 1996. In 1998, the mass death of pink salmon was in the north of the Khabarovsk Territory in the Amgun River. Then, in both cases, the cause of the pestilence was abnormally warm water in the rivers and their tributaries.
“The current mass death of red fish still remains a mystery to specialists, since there are still no versatile laboratory studies and conclusions. One thing is known so far that no oil and chemical spills or other unfavorable environmental factors have been registered in the Amur recently,”the agency's source said.
So far, the scientist stressed, it is impossible to unequivocally name the reasons for the mass death of salmon. To determine the exact cause, it is necessary to conduct versatile laboratory tests. Therefore, until conclusions are received on the basis of versatile laboratory studies, all versions are conjectural.
“Most of the specialists monitoring the Amur, as well as scientists, are inclined to conclude that the mass death of salmon on the Amur is a consequence of two reasons: an unusually low water level in the river and its tributaries, and an unusually high water temperature for autumn. The hot dry summer not only deprived the Amur of its former powerful tributaries, but also warmed up the water in the taiga river almost to the bottom. Salmon loves cool water. In warm water, when huge schools of fish of several thousand individuals go to spawn. Salmon, experiencing tremendous stress in warm water, are thrown ashore and die,”said Voronov.
The reason for the mass death of salmon, the scientist specified, may also be the early arrival of stocks for spawning. Today the chum salmon arrived in Amur two weeks two weeks earlier than usual. Presumably, this is a huge herd a few years ago released into the Amur from the incubators of Chinese fish hatcheries, since the PRC tags were found on the chum salmon carcasses.
Promotional video:
“According to long-term observations, usually chum salmon, before entering the fresh waters of the Far Eastern rivers, waits in the coastal zone for a suitable temperature in spawning grounds. Today, in all likelihood, the behavior of the fish could be influenced by some so far unknown natural phenomena. Perhaps the salmon stocks have experienced stress in the seas, and their food supply in the feeding areas of the ocean has changed. It is not excluded that the cause of the mass pestilence was the global warming on the planet”, - said the director of the Institute of Water and Environmental Problems.