World War II Bombs, Torpedoes and Naval Mines: How Ocean Creatures Thrives on Abandoned Weapons

In the brackish waters off the Germany's shoreline lies a graveyard of Nazi bombs, torpedo heads and naval mines. Discarded from vessels at the conclusion of the second world war and forgotten about, numerous explosives have accumulated over the decades. They create a decaying carpet on the shallow, silty seafloor of the Bay of Lübeck in the western tip of the Baltic Sea.

Over the decades, the explosive stockpile was overlooked and neglected. A increasing amount of tourists traveled to the sandy beaches and tranquil sea for jetskiing, kite surfing and entertainment venues. Beneath the surface, the munitions decayed.

Researchers anticipated to see a barren area, with nothing living there because it was all contaminated, explains Andrey Vedenin.

When the first scientists went searching to see what they were doing to the ecosystem, the team expected to see a barren area, with nothing living there because it was all poisoned, states the lead researcher.

What they observed astonished them. Vedenin recounts his colleagues exclaiming in amazement when the submersible first sent the images back. It was a memorable occasion, he notes.

Thousands of sea creatures had made their homes amid the weapons, forming a renewed ecosystem denser than the sea floor surrounding it.

This ocean community was evidence to the tenacity of life. Truly surprising how much life we observe in locations that are expected to be toxic and risky, he says.

More than 40 starfish had piled on to one exposed piece of TNT. They were living on metal shells, ignition chambers and transport cases just centimetres from its dangerous content. Fish, crabs, anemones and bivalves were all found on the historic weapons. You could compare it with a reef ecosystem in terms of the abundance of fauna that was present, notes Vedenin.

Remarkable Population Density

An mean of more than forty thousand animals were dwelling on every meter squared of the munitions, scientists reported in their paper on the observation. The nearby seabed was much sparser, with only eight thousand individuals on every meter squared.

It is surprising that items that are designed to destroy everything are drawing so much marine organisms, explains Vedenin. You can see how the natural world adjusts after a catastrophic event such as the World War II and how, in some way, life finds its way to the most risky places.

Man-made Structures as Marine Habitats

Man-made constructions such as sunken vessels, offshore windfarms, oil rigs and pipelines can create alternatives, restoring some of the removed habitat. This study shows that munitions could be comparably advantageous – the explosion of life on those in the Lübeck Bay is likely to be found in different areas.

Between the late 1940s and 1948, 1.6m tons of munitions were discarded off the Germany's coast. Countless of individuals placed them in boats; some were deposited in specific areas, others just discarded at sea during transport. This is the first time researchers have recorded how marine life has reacted.

Worldwide Examples of Marine Adaptation

• In the United States, decommissioned drilling platforms have transformed into coral reefs
• Shipwrecks from the first world war have become environments for marine life along the Potomac in Maryland
• Tank tracks that have become environment to coral off Asan beach in the Pacific island

These places become even more important for marine life as the seas are increasingly denuded by commercial fishing, seafloor dredging and boat mooring. Shipwrecks and weapons dump sites essentially act as protected areas – they are not official reserves, but virtually any kind of human activity is prohibited, explains Vedenin. As a result a lot of species that are usually uncommon or decreasing, such as the cod fish, are flourishing.

Future Considerations

Wherever armed conflict has happened in the recent history, surrounding seas are often containing weapons, states Vedenin. Many millions of tons of dangerous substances rest in our marine environments.

The sites of these weapons are poorly documented, partially because of national borders, classified military information and the reality that records are hidden in historic archives. They present an explosion and safety hazard, as well as threat from the ongoing release of hazardous substances.

As Germany and additional nations embark on extracting these remains, experts hope to protect the habitats that have established around them. In the Lübeck Bay munitions are already being cleared.

It would be wise to substitute these iron structures left from weapons with some less dangerous, various non-dangerous materials, like maybe artificial reefs, says Vedenin.

He now hopes that what occurs in Lübeck creates a model for replacing habitats after weapon clearance elsewhere – because also the most damaging armaments can become scaffolding for new life.