World War II Bombs, Torpedo Heads and Mines: How Ocean Creatures Flourishes on Dumped Weapons

In the slightly salty sea off the German shoreline lies a collection of Nazi bombs, torpedo heads and mines. Dumped from vessels at the conclusion of the World War II and left behind, numerous weapons have fused into clusters over the years. They form a decaying carpet on the low-depth, silty seafloor of the Lübeck Bay in the western part of the Baltic.

Over the years, the Nazi arsenal was overlooked and neglected. A increasing amount of visitors traveled to the coastal areas and tranquil sea for water sports, kiteboarding and amusement parks. Underwater, the munitions decayed.

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

When the team went looking to see what they were doing to the ecosystem, researchers anticipated finding a lifeless zone, with no life because it was all poisoned, explains the lead researcher.

What they found amazed them. Vedenin recalls his colleagues reacting with shock when the ROV first sent the images back. That moment was a remarkable experience, he recalls.

Countless of ocean life had established habitats amid the weapons, creating a revitalized marine community denser than the seabed around it.

This ocean community was evidence to the tenacity of marine life. Truly astonishing how much marine organisms we discover in locations that are supposed to be toxic and harmful, he says.

More than 40 sea stars had gathered on to one exposed fragment of explosive material. They were dwelling on iron containers, fuse pockets and storage boxes just a short distance from its dangerous content. Marine fish, crustaceans, sea anemones and bivalves were all found on the historic weapons. It's similar to a marine reef in terms of the amount of fauna that was there, notes Vedenin.

Remarkable Population Density

An average of more than forty thousand creatures were dwelling on every square metre of the munitions, scientists wrote in their study on the observation. The surrounding area was much less diverse, with only 8,000 individuals on every meter squared.

It is paradoxical that objects that are designed to eliminate everything are attracting so much marine organisms, explains Vedenin. One can observe how nature adjusts after a major disaster such as the second world war and how, in some way, life establishes itself to the most risky places.

Artificial Features as Ocean Environments

Artificial constructions such as shipwrecks, offshore windfarms, oil rigs and undersea pipes can offer substitutes, replacing some of the lost habitat. This investigation demonstrates that explosives could be similarly beneficial – the explosion of marine organisms on those in the Lübeck Bay is expected to be repeated in other locations.

Between 1946 and the post-war period, 1.6 million tons of munitions were discarded off the Germany's coast. Numerous of individuals transported them in boats; some were dropped in allocated areas, the remainder just dumped en route. This is the first time researchers have documented how ocean organisms has adapted.

Global Instances of Marine Adaptation

• In the US, decommissioned oil and gas structures have become reef ecosystems
• Shipwrecks from the World War I have become environments for marine life along the Potomac River in the state of Maryland
• Military vehicle parts that have become environment to coral off Asan beach in the Pacific island

These places become even more valuable for marine life as the oceans are increasingly stripped by commercial fishing, bottom trawling and anchoring. Sunken ships and explosive disposal locations practically act as protected areas – they are not national parks, but virtually any kind of human activity is prohibited, says Vedenin. As a result a many of organisms that are usually uncommon or declining, such as the Baltic cod, are thriving.

Future Considerations

Wherever military conflict has taken place in the recent history, surrounding seas are typically littered with munitions, explains Vedenin. Millions of tonnes of explosive material rest in our marine environments.

The sites of these munitions are poorly mapped, in part because of sovereign limits, restricted armed forces records and the fact that records are buried in old files. They present an detonation and security hazard, as well as threat from the ongoing release of hazardous substances.

As Germany and other countries start clearing these artifacts, experts aim to preserve the marine communities that have established nearby. In the Lübeck Bay weapons are already being removed.

We should replace these steel remains left from munitions with certain less dangerous, some safe structures, like possibly concrete structures, suggests Vedenin.

He now wishes that what occurs in the Bay of Lübeck establishes a precedent for substituting structures after munitions removal elsewhere – because also the most damaging armaments can become framework for new life.