Nazi Explosives, Torpedoes and Mines: The Way Marine Life Flourishes on Abandoned Weapons

In the brackish waters off the German coast lies a graveyard of Nazi bombs, torpedo heads and naval mines. Discarded from boats at the conclusion of the second world war and left behind, countless explosives have become matted together over the decades. They create a decaying carpet on the low-depth, silty seafloor of the Bay of Lübeck in the western part of the Baltic.

Over the decades, the Nazi arsenal was ignored and neglected. A growing number of visitors traveled to the sandy beaches and calm waters for jetskiing, kiteboarding and amusement parks. Below the waves, the weapons eroded.

Some of us thought to see a barren area, with nothing living there because it was all toxic, says the lead researcher.

When the initial researchers went searching to see what they were affecting to the ecosystem, researchers anticipated finding a barren area, with no organisms because it was all poisoned, says Andrey Vedenin.

What they discovered amazed them. Vedenin remembers his colleagues shouting with surprise when the ROV first sent the images back. It was a great moment, he says.

Numerous of marine animals had established habitats among the munitions, creating a renewed marine community denser than the sea floor around it.

This marine city was testament to the persistence of life. Truly surprising how much life we find in places that are supposed to be dangerous and harmful, he states.

Over 40 starfish had gathered on to one accessible chunk of TNT. They were dwelling on steel casings, ignition chambers and carrying containers just centimetres from its volatile core. Marine fish, crabs, anemones and bivalves were all found on the discarded explosives. It's similar to a reef ecosystem in terms of the amount of animal life that was inhabiting the area, notes Vedenin.

Surprising Population Density

An average of more than 40,000 creatures were dwelling on every square metre of the weapons, researchers wrote in their study on the finding. The adjacent region was much less diverse, with only eight thousand individuals on every meter squared.

It is paradoxical that objects that are intended to eliminate all life are drawing so much marine organisms, says Vedenin. You can see how the natural world adapts after a major disaster such as the World War II and how, in some way, marine life returns to the most risky locations.

Artificial Structures as Marine Environments

Man-made structures such as sunken vessels, wind turbines, drilling platforms and undersea pipes can create replacements, replacing some of the destroyed habitat. This investigation reveals that explosives could be equally beneficial – the explosion of marine organisms on those in the Lübeck Bay is likely to be duplicated elsewhere.

Between the late 1940s and the post-war period, 1.6 million tonnes of munitions were disposed of off the Germany's shoreline. Thousands of individuals loaded them in barges; some were dropped in allocated sites, the remainder just discarded at sea during transport. This is the initial instance scientists have documented how ocean organisms has reacted.

Global Instances of Ocean Adaptation

• In the US, retired drilling platforms have transformed into coral reefs
• Shipwrecks from the first world war have become environments for marine life along the Potomac River in Maryland
• Tank tracks that have become home to reef-building organisms off Asan in Guam

These locations become even more valuable for marine life as the seas are increasingly stripped by commercial fishing, bottom trawling and anchoring. Shipwrecks and weapons dump sites effectively act as sanctuaries – they are not national parks, but virtually any kind of human activity is banned, explains Vedenin. Consequently a lot of marine species that are typically uncommon or declining, such as the Baltic cod, are flourishing.

Coming Factors

Anywhere warfare has occurred in the last century, nearby oceans are usually strewn with weapons, states Vedenin. Millions of tons of explosive material lie in our oceans.

The locations of these explosives are insufficiently mapped, in part because of international boundaries, classified armed forces records and the reality that records are buried in historic archives. They create an explosion and security hazard, as well as risk from the continuous release of hazardous substances.

As Germany and different states start removing these relics, experts aim to preserve the habitats that have established nearby. In the Bay of Lübeck munitions are presently being extracted.

Researchers recommend substitute these metal carcasses left from weapons with certain less dangerous, some safe objects, like maybe concrete structures, says Vedenin.

He now hopes that what occurs in the Bay of Lübeck creates a example for substituting material after explosive extraction elsewhere – because also the most destructive weaponry can become framework for new life.