In the Black Sea Porpoises and Dolphins Struggle to Survive Year of Russian Invasion

Every year, a small group of harbour porpoises traverses a narrow strait from the Black Sea to the Sea of Asov, then returns again, in a natural migration cycle. Since prehistory, these Black Sea porpoises have been isolated, evolving separately from other porpoises, becoming smaller, but with larger snouts. They’re sleek and cute, with eyes and mouths that have the perpetual hint of a smile.

Text: Elyse Hauser

While they may look unbothered, life is actually very difficult for these porpoises. Their small population has been in decline for years due to human impacts like coastal infrastructure and pollution. But they’ve faced unprecedented risks since 2022, when Russia’s full-scale war on Ukraine began.

Today, military actions continue to threaten these unique porpoises, other cetaceans like bottlenose and common dolphins, and all the life connected to them in the Black Sea. So far, Ukraine’s successes in the war have allowed the delicate Black Sea ecosystems to persist. Yet many threats remain, from obvious violence to obscure pollutants, which may not be fully understood until the war eventually ends. 

Danger and poison

The loud, obvious threats include bombs blasting and missiles launching. “One of the main tools for Russia is shelling Ukraine with missiles from the submarines and naval ships from the Black Sea,” says Pavel Gol’din, lead researcher at National Academy of Sciences of Ukraine, who focuses on marine mammals. In addition to the physical danger, porpoises and dolphins are threatened by the noise from military strikes, which disrupts their ability to communicate, navigate, and hunt. Even sounds from military planes flying overhead can be harmful.

Not only are missiles loud, with deadly strikes, but their fuel is also toxic. Every time Russia fuels up a missile for launch, there’s a chance that some fuel spills into the sea. Plus, many missiles fall into the sea instead of reaching their targets. The toxic fuel’s chemical pollution will likely linger long after the fighting ends.   

The effects of military destruction elsewhere can reach the Black Sea, too. When the Kakhovka Dam was destroyed in 2023, it unleashed a flood of freshwater that traveled from river to sea. The water picked up pollution on its way, and it may also have carried bacteria or viruses that Black Sea life isn’t prepared to contend with. Only with time will the full effects of the deluge become clear.

While pollutants and pathogens can harm all kinds of marine life, the risks are especially severe for marine mammals. As top predators, they consume harmful substances from everything below them on the food web. “They are quite good indicators about the general health of this ecosystem,” says Dimitar Popov, project manager at Green Balkans, a conservation-focused NGO in Bulgaria. When these apex predators die, as many have due to the war, this means the entire ecosystem has been harmed.

No freedom to travel

Marine mammals are also at high risk from war because they migrate. Wartime actions and infrastructure have obstructed natural pathways through the Black Sea. For example, when Russia built a bridge across the Kerch Strait, it barricaded the cetaceans’ migration path between the Black Sea and the Sea of Asov.

Russian threats stretch to other parts of the Black Sea, too. Dangerous sea mines often travel far from where they’re expected: they’ve been found in Bulgarian, Türkish, and even Russian waters.[13] “Probably these mines were designed to be anchored, but many of them got released from their anchors, and now they’re drifting across the sea,” says Gol’din. Some will likely continue to drift, posing threats across the sea for years to come.

Porpoises and dolphins can travel to avoid some threats. Still, there’s no replacement for the Ukrainian waters where they often naturally congregate. “In the Ukrainian part of the Black Sea, the habitats are really important because it’s the widest and largest part of the [continental] shelf, and it has been traditionally very good spawning ground for a lot of the fish species,” says Popov. This makes it excellent hunting territory for the cetaceans. But the war has forced them away.

Good research is blocked

Russian aggression hasn’t just kept animals away from the waters they depend on. It’s also kept Ukrainian scientists away. “It’s horrible, because we are very limited in our capacities,” says Gol’din.

Researchers can no longer travel to many of the Black Sea ecological sites. Instead, they compensate by collecting dead, stranded dolphins and porpoises for lab research.

Ukrainian researchers also collaborate with colleagues in other countries, like Bulgaria, where at-sea research is safer. “We have a cooperation with all the Black Sea countries except Russia,” says Gol’din. Ukrainian scientists can take part, for example, by analyzing data collected by scientists elsewhere.

Without fieldwork from Ukraine, researchers can’t know the full status of Black Sea ecosystems. Still, they’ve noticed some patterns as marine mammals navigate the war’s risks. “We have seen clearly some signs of impact in the first year, in 2022, when the number of strandings was very high,” Popov recalls. Strandings are when marine mammals get washed ashore, often due to injury or illness. The experts suspected these strandings were caused by acoustic trauma: the damaging noise from explosions, ships, and planes. They also saw more live porpoises in Bulgarian waters that year, likely because they’d fled south from the threats.

Hope and uncertainty for the future

When the full-scale war began in 2022, the entire Black Sea was laden with Russian military vessels. But Ukraine’s destroyed many war vessels since then, and worked to push the rest eastward. “Now most of these ships and submarines, they are located in the northeastern Black Sea, not in the whole sea area,” says Gol’din. This gives marine mammals space to recover. Still, researchers can’t be sure whether the cetaceans have returned to Ukrainian waters. “Until the war is over and a proper survey is done in the Ukrainian office, it will not be possible to say for sure that animals are there, and that they are using this important habitat,” says Popov.
                     

Ukraine’s successes so far offer hope across the entire Black Sea. In the war, Ukrainians fight not just for human life, but for all the other lifeforms that share their home region. Black Sea marine mammals have nowhere else to go: the dolphins and porpoises are unique subspecies.
Should they go extinct, there will be nothing else like them on Earth. “For each of them,” says Gol’din, “the Black Sea is the only place in the world where they can live.”

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