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

In the brackish waters off the Germany's shoreline rests a wasteland of World War II explosives, torpedo heads and mines. Discarded from barges at the end of the second world war and left behind, countless explosives have fused into clusters over the years. They form a rusting blanket on the shallow, silty ocean floor of the Lübeck Bay in the western tip of the Baltic.

Over the years, the Nazi arsenal was overlooked and neglected. A growing number of tourists came to the sandy beaches and tranquil sea for water sports, kite surfing and entertainment venues. Below the waves, the weapons eroded.

Researchers thought to see a desert, with no organisms because it was all contaminated, states the lead researcher.

When the first scientists went searching to see what they were affecting to the marine environment, some of us anticipated finding a barren area, with no organisms because it was all contaminated, explains Andrey Vedenin.

What they found surprised them. Vedenin remembers his scientists exclaiming in amazement when the ROV first transmitted footage. This was a great moment, he recalls.

Thousands of sea creatures had established habitats amid the explosives, forming a renewed habitat richer than the sea floor nearby.

This marine city was testament to the tenacity of life. Truly surprising how much marine organisms we discover in locations that are expected to be toxic and dangerous, he says.

Over 40 starfish had clustered on to one accessible chunk of explosive material. They were dwelling on metal shells, fuse pockets and storage boxes just centimetres from its dangerous content. Fish, crabs, sea anemones and bivalves were all found on the discarded explosives. It resembles a coral reef in terms of the abundance of fauna that was present, says Vedenin.

Unexpected Population Density

An mean of more than 40,000 creatures were dwelling on every square metre of the munitions, experts documented in their paper on the finding. The nearby seabed was much less diverse, with only 8,000 individuals on every square metre.

It is paradoxical that items that are designed to destroy all life are drawing so much life, states Vedenin. You can see how the natural world adapts after a major disaster such as the second world war and how, in some way, life establishes itself to the most hazardous locations.

Artificial Structures as Ocean Environments

Man-made features such as sunken vessels, wind turbines, oil rigs and undersea pipes can provide alternatives, replacing some of the destroyed habitat. This research reveals that explosives could be comparably beneficial – the explosion of life on those in the Bay of Lübeck is expected to be found in other locations.

Between 1946 and the post-war period, 1.6 million tonnes of munitions were disposed of off the Germany's coast. Numerous of individuals placed them in vessels; a portion were placed in designated locations, others just thrown overboard during transport. This is the initial instance scientists have studied how ocean organisms has reacted.

Global Examples of Ocean Adaptation

• In the United States, decommissioned oil and gas structures have become coral reefs
• Shipwrecks from the first world war have become habitats for marine life along the Potomac in the state of Maryland
• Tank tracks that have become home to coral off Asan in Guam

These areas become even more valuable for organisms as the seas are increasingly denuded by commercial fishing, bottom trawling and anchoring. Sunken ships and weapons dump sites effectively function as refuges – they are not national parks, but almost any kind of anthropogenic disturbance is prohibited, says Vedenin. As a result a many of marine species that are usually rare or declining, such as the Baltic cod, are flourishing.

Coming Factors

Wherever armed conflict has occurred in the last century, nearby oceans are typically strewn with weapons, states Vedenin. Millions of tons of explosive material lie in our marine environments.

The sites of these munitions are inadequately documented, in part because of international boundaries, classified armed forces records and the fact that archives are hidden in old files. They pose an explosion and security risk, as well as danger from the persistent leakage of poisonous compounds.

As Germany and other countries start extracting these remains, experts plan to preserve the ecosystems that have developed nearby. In the Lübeck Bay explosives are already being extracted.

It would be wise to substitute these steel remains left from weapons with certain more secure, some safe objects, like possibly concrete structures, says Vedenin.

He now hopes that what transpires in Lübeck sets a model for substituting habitats after explosive extraction in different areas – because including the most damaging explosives can become foundation for ocean ecosystems.