World War II Explosives, Torpedo Heads and Mines: The Way Ocean Creatures Thrives on Discarded Weapons

In the slightly salty waters off the German shoreline rests a graveyard of World War II explosives, torpedo heads and naval mines. Thrown off boats at the end of the second world war and forgotten about, thousands weapons have fused into clusters over the years. They comprise a rusting blanket on the shallow, silty seafloor of the Bay of Lübeck in the western part of the Baltic Sea.

Over the years, the explosive stockpile was ignored and neglected. A growing number of visitors traveled to the coastal areas and calm waters for water sports, kiteboarding and entertainment venues. Beneath the surface, the munitions deteriorated.

Researchers expected to see a barren area, with no life because it was all contaminated, says the lead researcher.

When the first scientists went investigating to see what they were affecting to the marine environment, researchers thought they would find a desert, with nothing living there because it was all poisoned, explains a scientist.

What they found surprised them. Vedenin recounts his scientists exclaiming in amazement when the submersible first transmitted footage. It was a memorable occasion, he says.

Countless of marine animals had established habitats on the explosives, forming a renewed ecosystem denser than the ocean bottom surrounding it.

This marine city was testament to the tenacity of marine life. It is actually remarkable how much marine organisms we discover in locations that are supposed to be dangerous and risky, he explains.

Over 40 sea stars had gathered on to one exposed fragment of TNT. They were residing on metal shells, ignition chambers and storage boxes just a short distance from its explosive filling. Fish, crabs, sea anemones and mussels were all discovered on the old munitions. It resembles a reef ecosystem in terms of the amount of animal life that was inhabiting the area, notes Vedenin.

Unexpected Population Density

An mean of more than 40,000 animals were dwelling on every square metre of the weapons, researchers documented in their research on the observation. The nearby seabed was much less diverse, with only 8,000 individuals on every meter squared.

It is ironic that items that are intended to eliminate all life are hosting so much life, says Vedenin. It's evident how nature adjusts after a catastrophic event such as the second world war and how, in some way, marine life establishes itself to the most risky areas.

Man-made Structures as Marine Environments

Artificial features such as sunken vessels, wind turbines, oil rigs and pipelines can create alternatives, compensating for some of the destroyed marine environment. This study demonstrates that munitions could be equally beneficial – the explosion of marine organisms on those in the Lübeck Bay is likely to be found in different areas.

Between 1946 and the post-war period, 1.6 million tons of munitions were dumped off the German coast. Thousands of people transported them in vessels; some were placed in designated sites, the remainder just thrown overboard during transport. This is the first time researchers have studied how ocean organisms has responded.

Worldwide Examples of Ocean Adaptation

• In the United States, retired oil and gas structures have turned into coral reefs
• Shipwrecks from the first world war have become homes for wildlife along the Potomac in the state of Maryland
• Tank tracks that have become habitat to reef-building organisms off Asan in the Pacific island

These areas become even more valuable for organisms as the seas are increasingly denuded by fishing, seafloor dredging and boat mooring. Shipwrecks and munitions areas essentially act as sanctuaries – they are not national parks, but virtually any kind of human activity is prohibited, says Vedenin. Therefore a lot of marine species that are typically rare or decreasing, such as the cod fish, are prospering.

Coming Considerations

Anywhere military conflict has taken place in the last century, adjacent waters are often containing explosives, states Vedenin. Many millions of tons of explosive material lie in our marine environments.

The positions of these explosives are inadequately documented, partly because of sovereign limits, secret armed forces records and the situation that archives are buried in historical records. They present an detonation and security hazard, as well as danger from the ongoing emission of hazardous substances.

As the German government and other countries start removing these artifacts, scientists plan to protect the marine communities that have established around them. In the Bay of Lübeck explosives are already being cleared.

We should replace these steel remains left from munitions with certain safer, various non-dangerous objects, like maybe concrete structures, says Vedenin.

He now hopes that what happens in Lübeck establishes a precedent for replacing structures after explosive extraction in different areas – because including the most destructive weaponry can become scaffolding for marine organisms.