The season of cetacean strandings has begun in the Black Sea. Sick and dead dolphins continue to be found along the coast daily. According to the latest statistics, 132 dead individuals have been recorded since the beginning of March!
At the end of April, social media reported that several dead dolphins had washed ashore in the Lazarevsky District of Sochi and in the village of Golubitskaya (Temryuk District). However, the Scientific and Ecological Center for Dolphin Rescue "Delphia" has no such information for these locations so far.
"We cannot pinpoint anything specifically there — we do not have such data. But reports are coming in from everywhere along the coast: Tuapse, Sochi, Gelendzhik, Abkhazia. Not always only fresh bodies, not always only old ones — different. We publish the overall picture on social media."
Overall, according to the rescue center, the situation looks like this: since the beginning of March, volunteers have recorded 132 dead individuals from Taman to Sirius. In the first ten days of April alone — 82 dolphins. The most findings were in Novorossiysk: 20 in March and 37 in early April.
What is Really Killing Dolphins
The "Delphia" center directly points to the most likely cause of spring mortality — bycatch. Dolphins die in fishing nets, especially in flatfish nets, the season for which lasts until the end of April. Clear signs of nets were found on 23 animals (17.4% of all findings): cuts on the skin, worn fins, severed limbs. The real percentage, according to experts, is significantly higher, as many bodies have decomposed to the point that identifying traces is impossible.
However, nets are not the only threat. Ecologist Veniamin Golubitchenko explained the mechanism of injuries:
"First of all, when it comes to mechanical damage, dolphins get injured by nets. In second place are injuries from ship, boat, and motorboat propellers. They are curious, often swim up to yacht marinas and ports — and can get caught in a propeller."
Another factor is high acoustic load:
"If a dolphin enters a zone of high acoustic load, it can suffer a concussion — brain damage, a concussion with a rupture of the auditory ligaments. It sustains serious injury, cannot feed for a long time, weakens, and dies."
"Currently, there is active mixing of flora and fauna. People bring dolphins from northern and far eastern seas, keep them together in aquariums — they transmit diseases and parasites to each other. What was not noted before may be related either to insufficient study or to the emergence of a new parasite for the region."
According to him, the parasite itself is not always lethal — immunity plays a crucial role.
Which is More Dangerous: Nets or Pollution?
So what is more detrimental to the population of Black Sea dolphins — fishing or pollution? Golubitchenko's answer shows that the problem is not due to a single factor:
"Both pollution and fishing, and everything else act simultaneously and in the same direction. If both fishing and pollution — they overlap and amplify the negative impact. If one factor is removed — the situation will improve only slightly."
The only systemic solution is to reduce all factors at once. But until that is achieved, volunteers and scientists can only record the losses.
