Nazi Explosives, Torpedoes and Mines: The Way Marine Life Prosper on Abandoned Armaments

In the brackish sea off the Germany's coast rests a collection of Nazi bombs, torpedoes and naval mines. Thrown off vessels at the end of the second world war and forgotten about, thousands weapons have fused into clusters over the decades. They comprise a corroding layer on the shallow, muddy ocean floor of the Bay of Lübeck in the western tip of the Baltic Sea.

Over the years, the wartime weapons was overlooked and forgotten about. A increasing amount of tourists came to the coastal areas and calm waters for water sports, kiteboarding and amusement parks. Beneath the surface, the weapons eroded.

We initially expected to see a barren area, with no organisms because it was all toxic, states the lead researcher.

When the initial researchers went looking to see what they were doing to the ecosystem, researchers expected to see a desert, with nothing living there because it was all poisoned, states the lead researcher.

What they discovered amazed them. Vedenin remembers his team members shouting with surprise when the underwater vehicle first relayed pictures. It was a memorable occasion, he notes.

Countless of ocean life had made their homes among the munitions, creating a renewed marine community denser than the seabed around it.

This marine city was testament to the tenacity of marine life. Indeed surprising how much life we find in places that are considered toxic and dangerous, he states.

Over 40 sea stars had clustered on to one accessible piece of explosive material. They were residing on steel casings, detonator compartments and storage boxes just a short distance from its dangerous content. Fish, crabs, anemones and bivalves were all observed on the historic weapons. It resembles a reef ecosystem in terms of the abundance of animal life that was inhabiting the area, notes Vedenin.

Surprising Population Density

An mean of more than forty thousand animals were living on every square metre of the weapons, scientists documented in their research on the discovery. The adjacent region was much sparser, with only eight thousand creatures on every square metre.

It is surprising that items that are designed to destroy all life are attracting so much marine organisms, says Vedenin. It's evident how nature evolves after a devastating occurrence such as the second world war and how, in certain respects, life finds its way to the most dangerous locations.

Man-made Features as Ocean Habitats

Artificial features such as sunken vessels, wind turbines, oil rigs and undersea pipes can offer alternatives, restoring some of the lost habitat. This research shows that weapons could be equally positive – the proliferation of marine organisms on those in the Bay of Lübeck is probable to be found elsewhere.

Between the late 1940s and the post-war period, 1.6m tons of munitions were dumped off the German coast. Thousands of individuals loaded them in barges; some were placed in allocated locations, others just thrown overboard during transport. This is the initial instance researchers have recorded how marine life has responded.

Global Instances of Marine Adaptation

• In the United States, decommissioned energy installations have transformed into marine habitats
• Shipwrecks from the World War I have become homes for wildlife along the Potomac River in the state of Maryland
• Tank tracks that have become environment to coral off Asan in Guam

These places become even more valuable for marine life as the oceans are increasingly denuded by fishing, seafloor dredging and anchoring. Shipwrecks and weapons dump sites practically act as sanctuaries – they are not national parks, but virtually any kind of anthropogenic disturbance is banned, states Vedenin. Consequently a lot of organisms that are otherwise scarce or declining, such as the Baltic cod, are prospering.

Coming Factors

Wherever armed conflict has occurred in the recent history, nearby oceans are often strewn with munitions, explains Vedenin. Millions of tons of volatile compounds lie in our oceans.

The locations of these munitions are inadequately documented, in part because of sovereign limits, restricted defense data and the fact that documents are stored in historic archives. They create an detonation and security risk, as well as danger from the persistent release of toxic chemicals.

As the German government and other countries start extracting these relics, researchers aim to safeguard the ecosystems that have formed nearby. In the Bay of Lübeck explosives are already being extracted.

It would be wise to replace these iron structures originating from weapons with some more secure, some harmless objects, like possibly artificial reefs, suggests Vedenin.

He now wishes that what transpires in the Bay of Lübeck sets a example for substituting material after munitions removal in other locations – because also the most damaging armaments can become foundation for marine organisms.