World War II Bombs, Torpedo Heads and Naval Mines: How Marine Life Prosper on Discarded Weapons

In the slightly salty waters off the Germany's shoreline sits a collection of World War II explosives, torpedo heads and mines. Thrown off vessels at the conclusion of the World War II and left behind, thousands explosives have fused into clusters over the years. They form a rusting carpet on the low-depth, silty ocean floor of the Bay of Lübeck in the western part of the Baltic Sea.

Over the years, the wartime weapons was ignored and forgotten about. A growing number of tourists flocked to the coastal areas and calm waters for jetskiing, kiteboarding and entertainment venues. Underwater, the munitions eroded.

Researchers expected to see a desert, with no organisms because it was all contaminated, says Andrey Vedenin.

When the first scientists went looking to see what they were affecting to the marine environment, some of us thought they would find a desert, with no organisms because it was all contaminated, states Andrey Vedenin.

What they discovered amazed them. Vedenin recounts his team members exclaiming in amazement when the ROV first transmitted footage. That moment was a remarkable experience, he recalls.

Countless of sea creatures had made their homes among the weapons, developing a revitalized habitat more populous than the sea floor surrounding it.

This underwater metropolis was proof to the tenacity of marine life. Indeed astonishing how much life we observe in locations that are supposed to be toxic and harmful, he states.

More than 40 sea stars had clustered on to one exposed fragment of explosive material. They were residing on steel casings, detonator compartments and transport cases just a short distance from its volatile core. Marine fish, crabs, anemones and bivalves were all observed on the discarded explosives. It's similar to a coral reef in terms of the amount of creatures that was inhabiting the area, states Vedenin.

Surprising Population Density

An mean of more than forty thousand animals were living on every meter squared of the weapons, researchers reported in their paper on the observation. The surrounding area was much poorer in life, with only 8,000 individuals on every meter squared.

It is paradoxical that items that are meant to eliminate all life are drawing so much life, explains Vedenin. One can observe how nature adapts after a major disaster such as the second world war and how, in some way, life finds its way to the most hazardous locations.

Artificial Features as Marine Environments

Artificial features such as shipwrecks, wind turbines, drilling platforms and undersea pipes can create alternatives, compensating for some of the lost habitat. This study demonstrates that explosives could be similarly advantageous – the explosion of marine organisms on those in the Bay of Lübeck is likely to be repeated elsewhere.

Between the late 1940s and the post-war period, 1.6m tonnes of weapons were dumped off the German coast. Countless of workers placed them in boats; some were deposited in specific sites, others just thrown overboard while traveling. This is the first time experts have studied how ocean organisms has responded.

Global Examples of Ocean Transformation

• In the US, retired energy installations have become reef ecosystems
• Sunken ships from the World War I have become habitats for marine life along the Potomac in the state of Maryland
• Military vehicle parts that have become environment to reef-building organisms off Asan in Guam

These locations become even more valuable for wildlife as the marine environments are increasingly depleted by commercial fishing, seafloor dredging and boat mooring. Shipwrecks and explosive disposal locations effectively serve as protected areas – they are not national parks, but almost any kind of human activity is banned, states Vedenin. Consequently a lot of species that are usually rare or diminishing, such as the cod fish, are flourishing.

Future Considerations

Anywhere military conflict has taken place in the recent history, surrounding seas are usually littered with weapons, says Vedenin. Millions of tons of dangerous substances lie in our oceans.

The positions of these explosives are insufficiently recorded, partially because of international boundaries, restricted defense data and the fact that archives are buried in historical records. They pose an explosion and safety danger, as well as threat from the persistent release of poisonous compounds.

As Germany and different states embark on clearing these remains, researchers aim to protect the habitats that have developed nearby. In the Lübeck Bay explosives are already being removed.

We should substitute these steel remains originating from munitions with some less dangerous, various harmless materials, like maybe concrete structures, suggests Vedenin.

He now hopes that what transpires in Lübeck sets a precedent for substituting structures after weapon clearance elsewhere – because even the most destructive explosives can become foundation for marine organisms.