Ecology Ministry announces cause of mass die-off of Caspian seals
According to him, the carcasses of the dead seals were highly decomposed, which did not allow conducting any toxicological and virology tests, Kazinform correspondent reports.
In total, 220 dead seals were found in Karazhambas and in the southwestern part of the Tyub-Karagan peninsula in early 2022 , the Minister said. All the carcasses were driven to the coast by winds from the northern and middle Caspian basins.
The Kazakh Institute of Hydrobiology and Ecology, Research and Development Center of Microbiology and Virology, Kazakh Agency of Applied Ecology, research institutions and organizations, all stakeholders, local ecology departments and veterinary divisions were involved in this work.
The working group came to the following conclusion:
«Since the discovered carcasses of the seals were severely decomposed, the veterinary services of the Research and Development Center of Microbiology and Virology, as well as the above-mentioned institutions could not take tissues for toxicological, histological, and virology tests. The marine animals died several months ago,» the Minister told the press briefing.
Only 67 carcasses of the dead seals could be visually examined and measured, which revealed that around 25%, or 17 species, had traces of mechanical injuries on their bodies, which had led or could lead to their death. The causes of mechanical injuries could be by-catch of the seals into fishing nets, injuring live or dead seals during their disentanglement, and entanglement of seals in prohibited capturing tools.
Serikkali Brekeshev stressed that this is a barbaric way of fishing. Such tools are prohibited in Kazakhstan.
«We could identify the age of 19 seals only, 52% of which, or 10 were the pups born in the winter of 2021-2022. The die-off of pups is explained by their malnutrition, freezing due to falling into the cold water, and the removal of ice with newborn seals to the open sea. The warm winter of 2021-2022 was unfavorable for seal breeding on ice. Therefore, these facts caused natural death of the marine mammals. In general, the oldest seal found was 13 years old. All the discovered carcasses were disposed of in compliance with sanitary standards.
The Minister also commented on the link between the die-off of seals and dredging operations conducted by the NCOC.
«During dredging works, all required measures are taken to minimize their impact on marine organisms, including the Caspian seals. At the same time, air samples taken by the Department of Ecology of Mangistau region from the area where the dead seals had been found did not contain harmful substances. Water samples contained slight excesses of the maximum permissible concentration of nickel - about 400 mg per cubic decimeter,» Serikkali Brekeshev added.