World War II Munitions, Torpedoes and Mines: How Ocean Creatures Thrives on Abandoned Armaments

In the slightly salty waters off the Germany's shoreline rests a wasteland of Nazi bombs, torpedoes and naval mines. Dumped from vessels at the end of the second world war and neglected, thousands munitions have accumulated over the decades. They create a decaying blanket on the shallow, silty seafloor of the Lübeck Bay in the western part of the Baltic.

Over the years, the explosive stockpile was ignored and forgotten about. A increasing amount of tourists flocked to the coastal areas and calm waters for water sports, kite surfing and entertainment venues. Below the waves, the munitions decayed.

We initially anticipated to see a lifeless zone, with nothing living there because it was all contaminated, states Andrey Vedenin.

When the first scientists went looking to see what they were affecting to the ecosystem, researchers thought they would find a lifeless zone, with no organisms because it was all contaminated, explains the lead researcher.

What they discovered amazed them. Vedenin recalls his scientists shouting with surprise when the ROV first relayed pictures. That moment was a remarkable experience, he says.

Numerous of ocean life had established habitats among the explosives, creating a revitalized ecosystem denser than the sea floor around it.

This ocean community was evidence to the resilience of life. Indeed surprising how much life we discover in places that are expected to be dangerous and risky, he states.

More than 40 starfish had gathered on to one exposed piece of TNT. They were dwelling on iron containers, detonator compartments and carrying containers just a short distance from its dangerous content. Marine fish, crabs, sea anemones and bivalves were all discovered on the old munitions. You could compare it with a marine reef in terms of the quantity of fauna that was inhabiting the area, says Vedenin.

Unexpected Population Density

An mean of more than 40,000 organisms were residing on every square metre of the explosives, researchers wrote in their paper on the finding. The surrounding area was much less diverse, with only eight thousand individuals on every meter squared.

It is paradoxical that things that are meant to eliminate everything are hosting so much life, says Vedenin. One can observe how nature adapts after a major disaster such as the second world war and how, in certain respects, marine life returns to the most risky areas.

Artificial Structures as Ocean Habitats

Artificial structures such as shipwrecks, offshore windfarms, oil rigs and undersea pipes can offer alternatives, restoring some of the removed habitat. This research shows that munitions could be similarly positive – the proliferation of marine organisms on those in the Bay of Lübeck is expected to be repeated in different areas.

Between the late 1940s and the post-war period, 1.6 million tons of weapons were disposed of off the German coast. Thousands of workers transported them in vessels; some were placed in designated locations, the remainder just dumped en route. This is the initial instance researchers have recorded how marine life has responded.

Global Examples of Ocean Adaptation

• In the United States, decommissioned oil and gas structures have transformed into marine habitats
• Shipwrecks from the World War I have become habitats for wildlife along the Potomac River in Maryland
• Military vehicle parts that have become home to reef-building organisms off Asan beach in Guam

These areas become even more important for wildlife as the marine environments are increasingly denuded by commercial fishing, seafloor dredging and anchoring. Shipwrecks and munitions areas effectively serve as refuges – they are not official reserves, but nearly any kind of anthropogenic disturbance is prohibited, says Vedenin. Therefore a lot of marine species that are usually rare or diminishing, such as the Baltic cod, are flourishing.

Coming Considerations

Wherever armed conflict has occurred in the last century, surrounding seas are usually littered with weapons, says Vedenin. Millions of tonnes of explosive material rest in our oceans.

The sites of these munitions are inadequately documented, in part because of international boundaries, secret military information and the situation that documents are hidden in old files. They pose an explosion and safety hazard, as well as threat from the continuous release of toxic chemicals.

As the German government and other countries embark on extracting these artifacts, experts aim to safeguard the habitats that have established in their vicinity. In the Bay of Lübeck explosives are currently being extracted.

Researchers recommend replace these iron structures remaining from munitions with certain more secure, some non-dangerous objects, like possibly concrete structures, states Vedenin.

He now wishes that what transpires in the Bay of Lübeck establishes a model for replacing structures after explosive extraction in other locations – because including the most harmful armaments can become foundation for marine organisms.