The P. P. Shirshov Institute of Oceanology of the Russian Academy of Sciences, together with the Nature and People Foundation and the Moskvarium Center for Oceanography and Marine Biology, conducted a joint expedition to study cetaceans in the Bugayskaya Spit area.

The fieldwork was a continuation of a scientific program studying cetaceans in the northeastern Black Sea. In 2018-2020, the Institute of Oceanology of the Russian Academy of Sciences resumed this research after a thirty-year hiatus, and it is now being conducted amid heightened environmental attention to the region. The work focused on two areas: coastal observations of cetaceans and monitoring strandings of dead animals.

During visual observations, specialists recorded cetacean encounters, recorded group composition and behavioral data, and took photographs for subsequent photo identification and compilation of an individual catalog. Fifty-seven encounters of harbor porpoises and bottlenose dolphins were recorded in a water area stretching over 30 kilometers. The data collected will help understand the importance of the surveyed area for cetaceans.

Monitoring strandings of dead animals was an equally important task. A 35-kilometer stretch of coastline was surveyed, and more than 40 dead cetaceans of all three species inhabiting the Black Sea were found. A record was created for each animal found, recording the state of preservation of the remains, the nature of the injuries, body size, and, where possible, age and sex. Some of the discovered animals likely died earlier in the winter, but the sheer number of recorded finds in a relatively small area of ​​the coastline is alarming and highlights the need for a detailed analysis of the causes of mortality.

"A field laboratory was set up on the shore, where a veterinarian from the Moskvarium Center for Oceanography and Marine Biology performed autopsies on recently deceased animals. These types of cases are particularly important for research, as only recently deceased animals can provide high-quality tissue and organ samples that can help scientists understand the causes of cetacean mortality. This, in turn, allows for a more objective assessment of the population status and the possible impact of anthropogenic factors, including water pollution," noted Varvara Levitskaya, a junior researcher at the Marine Mammal Laboratory at the Shirshov Institute of Oceanology of the Russian Academy of Sciences and an expert of the Nature and People Foundation.

The work was carried out with the support of the company "Mondelez Rus" and the brand "Unifood".

Experts emphasize that only a systematic approach - a combination of observations of living populations and mortality analysis - allows for a more complete picture of the state of cetacean populations in the Black Sea.

The expedition's photography and video recording were carried out by Maxim Tolstoy, an employee of the Video studio of the IO RAS.