Nazi Bombs, Torpedoes and Naval Mines: How Marine Life Prosper on Discarded Weapons

In the slightly salty waters off the German shoreline lies a collection of World War II explosives, torpedoes and mines. Dumped from barges at the end of the second world war and neglected, thousands weapons have fused into clusters over the decades. They comprise a decaying layer on the shallow, muddy seafloor of the Bay of Lübeck in the western part of the Baltic Sea.

Over the years, the wartime weapons was ignored and neglected. A increasing amount of visitors flocked to the sandy beaches and tranquil sea for jetskiing, kiteboarding and amusement parks. Underwater, the weapons decayed.

Researchers anticipated to see a desert, with no organisms because it was all contaminated, says a scientist.

When the first scientists went looking to see what they were affecting to the marine environment, researchers expected to see a desert, with no life because it was all toxic, explains the lead researcher.

What they found astonished them. Vedenin remembers his scientists exclaiming in amazement when the ROV first transmitted footage. That moment was a remarkable experience, he recalls.

Thousands of ocean life had established habitats amid the weapons, creating a revitalized habitat denser than the sea floor nearby.

This underwater metropolis was evidence to the persistence of marine life. Indeed remarkable how much marine organisms we observe in areas that are supposed to be hazardous and dangerous, he says.

In excess of 40 sea stars had gathered on to one exposed piece of TNT. They were living on metal shells, fuse pockets and transport cases just a short distance from its volatile core. Fish, crustaceans, sea anemones and bivalves were all observed on the discarded explosives. You could compare it with a reef ecosystem in terms of the abundance of fauna that was present, notes Vedenin.

Surprising Population Density

An average of more than 40,000 creatures were dwelling on every meter squared of the munitions, researchers reported in their study on the discovery. The nearby seabed was much poorer in life, with only 8,000 creatures on every meter squared.

It is paradoxical that objects that are designed to kill all life are hosting so much life, says Vedenin. It's evident how the natural world adjusts after a catastrophic event such as the second world war and how, in certain respects, marine life returns to the most risky locations.

Man-made Structures as Marine Habitats

Man-made structures such as sunken vessels, offshore windfarms, drilling platforms and pipelines can create replacements, restoring some of the destroyed habitat. This study reveals that weapons could be similarly positive – the bloom of life on those in the Bay of Lübeck is likely to be found in different areas.

Between 1946 and 1948, 1.6 million tonnes of weapons were discarded off the German coast. Thousands of individuals loaded them in barges; some were deposited in allocated sites, the remainder just dumped en route. This is the first time researchers have documented how ocean organisms has responded.

Worldwide Instances of Ocean Adaptation

• In the United States, retired energy installations have become reef ecosystems
• Shipwrecks from the first world war have become environments for wildlife along the Potomac River in the state of Maryland
• Military vehicle parts that have become habitat to reef-building organisms off Asan beach in Guam

These places become even more important for wildlife as the oceans are increasingly stripped by fishing, seafloor dredging and anchoring. Shipwrecks and munitions areas essentially act as protected areas – they are not national parks, but virtually any kind of anthropogenic disturbance is restricted, states Vedenin. Consequently a numerous of organisms that are usually uncommon or declining, such as the cod fish, are prospering.

Future Factors

Anywhere armed conflict has taken place in the last century, nearby oceans are usually littered with weapons, states Vedenin. Many millions of tons of volatile compounds remain in our oceans.

The sites of these munitions are insufficiently mapped, partially because of sovereign limits, restricted defense data and the reality that documents are buried in historic archives. They pose an explosion and safety hazard, as well as threat from the continuous release of toxic chemicals.

As Germany and additional nations embark on removing these artifacts, researchers hope to protect the ecosystems that have developed around them. In the Lübeck Bay weapons are presently being removed.

Researchers recommend substitute these iron structures originating from weapons with certain more secure, various safe materials, like possibly man-made habitats, suggests Vedenin.

He currently hopes that what happens in Lübeck establishes a model for replacing structures after explosive extraction in other locations – because even the most harmful explosives can become foundation for marine organisms.