In October, the German oil tanker Annika was towed safely back to the port of Rostock in the Baltic Sea after it caught fire just an hour after its departure. Nobody was injured, and damage to the environment was averted.

According to environmental organization Greenpeace, Germany's Baltic Sea coasts are under constant threat, without the public taking much notice. Dilapidated Russian oil tankers sail through the Baltic Sea in international waters every day.

The environmental organization isn't the only one concerned about the coastal region.

Daniel Schneider is the chairman of the Bundestag's parliamentary group on maritime policy for Germany's center-left Social Democratic Party (SPD) . "The average age of the tankers is very high," Schneider told DW. "They are around 16 to 17 years old. They are poorly maintained, which means they have many technical defects. But above all, they are also inadequately insured. We already have several hundred ships on the sanctions list, and this list needs to be expanded."

He has called for intensified cooperation with states like Panama or Greece, under whose flags many of the old tankers are registered. Schneider argues these states should prohibit unseaworthy ships without sufficient insurance from obtaining a permit.

Greenpeace has put together a list of vessels longer than 180 meters (590 feet) they say should be urgently taken out of service. Of these, 192 had no insurance and had traveled the Baltic Sea at least once in the past 18 months, often toward India or China.

The shipping route northeast of Rostock is considered the most difficult and dangerous area in the Baltic Sea. Still, according to Greenpeace, the ships usually sail without local support or pilots.

Greenpeace has called for EU sanctions. "As soon as these tankers are on the sanctions list, they will no longer be used for Russian oil exports. And that's exactly what we need now," said Greenpeace activist Thilo Maack, a marine biologist.

After the Kremlin launched its full-fledged invasion of Ukraine in early 2022, Western countries, and especially the EU, imposed far-reaching sanctions on Russia. However, experts have argued that this has done little to reduce the volume of Russian crude oil exports.

Russia has allegedly assembled an entire fleet of vessels sailing under other countries' flags. They undertake what Maack calls "adventurous" actions on the open sea, decanting oil from one ship to another in order to disguise its Russian origin. According to Maack's estimates, Russia has invested around €10 billion ($11 billion) in a fleet of dilapidated tankers.

Russia assembles 'shadow fleet'

While overall shipping traffic on the Baltic Sea has declined since 2022, the traffic of Russia's "shadow fleet" has increased by 70%.

Concern is also mounting in Denmark. In the summer, the government in Copenhagen announced it wanted to examine whether Russian tanker traffic could be restricted or even banned. Moscow promptly insisted on old agreements on freedom of navigation in international waters, such as the Copenhagen Convention of 1857, which stipulates that all Danish straits are free for all commercial shipping.

Now, state governments in Germany's northeastern regions have decided to raise awareness and seek ways to take action to curb the number of dilapidated oil tankers traveling unchecked across the Baltic Sea.

This article was originally written in German.

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