World War II Munitions, Torpedo Heads and Naval Mines: How Ocean Creatures Prosper on Discarded Armaments

In the brackish sea off the Germany's shoreline rests a graveyard of Nazi bombs, torpedoes and mines. Dumped from vessels at the end of the second world war and left behind, countless munitions have become matted together over the decades. They comprise a corroding blanket on the shallow, silty seafloor of the Bay of Lübeck in the western tip of the Baltic Sea.

Over the years, the explosive stockpile was overlooked and forgotten about. A growing number of visitors flocked to the sandy beaches and calm waters for jetskiing, kiteboarding and amusement parks. Below the waves, the munitions eroded.

We initially thought to see a desert, with no life because it was all toxic, explains Andrey Vedenin.

When the first scientists went investigating to see what they were doing to the marine environment, some of us expected to see a lifeless zone, with no life because it was all poisoned, states the lead researcher.

What they discovered surprised them. Vedenin remembers his colleagues reacting with shock when the underwater vehicle first sent the images back. That moment was a remarkable experience, he says.

Numerous of sea creatures had established habitats among the weapons, developing a revitalized marine community richer than the ocean bottom surrounding it.

This underwater metropolis was proof to the persistence of life. Indeed remarkable how much marine organisms we observe in locations that are considered toxic and risky, he states.

More than 40 sea stars had piled on to one accessible fragment of TNT. They were residing on iron containers, fuse pockets and carrying containers just a short distance from its dangerous content. Marine fish, crustaceans, anemones and mussels were all observed on the discarded explosives. You could compare it with a marine reef in terms of the quantity of animal life that was there, says Vedenin.

Surprising Population Density

An average of more than 40,000 creatures were living on every square metre of the weapons, researchers reported in their study on the discovery. The nearby seabed was much less diverse, with only 8,000 individuals on every meter squared.

It is ironic that items that are meant to eliminate all life are attracting so much marine organisms, states Vedenin. It's evident how nature adjusts after a major disaster such as the second world war and how, in some way, marine life returns to the most risky places.

Artificial Structures as Ocean Environments

Artificial structures such as shipwrecks, offshore windfarms, oil rigs and pipelines can create alternatives, compensating for some of the removed marine environment. This investigation demonstrates that weapons could be comparably beneficial – the proliferation of marine organisms on those in the Bay of Lübeck is probable to be found in other locations.

Between 1946 and the post-war period, 1.6m tonnes of weapons were dumped off the German coast. Countless of people placed them in boats; a portion were deposited in specific areas, others just discarded at sea during transport. This is the first time scientists have studied how marine life has responded.

Worldwide Examples of Ocean Transformation

• In the US, retired drilling platforms have transformed into reef ecosystems
• Sunken ships from the first world war have become homes for creatures along the Potomac River in the state of Maryland
• Military vehicle parts that have become environment to coral off Asan in Guam

These locations become even more valuable for organisms as the marine environments are increasingly stripped by commercial fishing, bottom trawling and boat mooring. Sunken ships and munitions areas practically function as refuges – they are not national parks, but almost any kind of anthropogenic disturbance is prohibited, explains Vedenin. Consequently a numerous of species that are otherwise uncommon or diminishing, such as the Baltic cod, are thriving.

Future Considerations

Anywhere warfare has occurred in the recent history, surrounding seas are typically strewn with munitions, states Vedenin. Many millions of tons of volatile compounds remain in our marine environments.

The sites of these munitions are poorly mapped, in part because of international boundaries, secret military information and the reality that records are stored in historic archives. They create an explosion and security risk, as well as danger from the persistent leakage of toxic chemicals.

As Germany and additional nations embark on extracting these artifacts, scientists plan to preserve the habitats that have formed nearby. In the Bay of Lübeck munitions are currently being cleared.

We should replace these iron structures originating from weapons with certain less dangerous, some non-dangerous materials, like maybe artificial reefs, says Vedenin.

He presently aspires that what transpires in Lübeck creates a example for replacing habitats after explosive extraction elsewhere – because including the most harmful explosives can become scaffolding for ocean ecosystems.