Nazi Bombs, Torpedoes and Mines: The Way Marine Life Flourishes on Dumped Armaments

In the brackish waters off the Germany's coast sits a collection of World War II explosives, torpedoes and naval mines. Thrown off boats at the conclusion of the World War II and left behind, countless munitions have fused into clusters over the decades. They form a corroding carpet on the shallow, silty seafloor of the Bay of Lübeck in the western tip of the Baltic Sea.

Over the years, the wartime weapons was overlooked and forgotten about. A growing number of visitors flocked to the sandy beaches and calm waters for jetskiing, kite surfing and amusement parks. Underwater, the weapons deteriorated.

Researchers expected to see a desert, with nothing living there because it was all toxic, states the lead researcher.

When the first scientists went looking to see what they were doing to the marine environment, some of us expected to see a desert, with no organisms because it was all poisoned, says Andrey Vedenin.

What they discovered astonished them. Vedenin recounts his colleagues exclaiming in amazement when the underwater vehicle first transmitted footage. That moment was a remarkable experience, he says.

Thousands of marine animals had established habitats on the munitions, developing a revitalized ecosystem more populous than the seabed nearby.

This underwater metropolis was evidence to the tenacity of marine life. It is actually remarkable how much marine organisms we find in locations that are supposed to be toxic and risky, he explains.

More than 40 sea stars had gathered on to one accessible chunk of explosive material. They were dwelling on steel casings, fuse pockets and carrying containers just centimetres from its dangerous content. Fish, crustaceans, anemones and bivalves were all observed on the discarded explosives. It's similar to a reef ecosystem in terms of the quantity of fauna that was there, states Vedenin.

Surprising Creature Concentration

An average of more than 40,000 creatures were dwelling on every square metre of the munitions, researchers reported in their paper on the finding. The nearby seabed was much sparser, with only eight thousand organisms on every meter squared.

It is ironic that items that are meant to kill all life are drawing so much life, says Vedenin. One can observe how nature adjusts after a devastating occurrence such as the World War II and how, in certain respects, life returns to the most risky areas.

Man-made Structures as Ocean Habitats

Artificial structures such as sunken vessels, offshore windfarms, oil rigs and pipelines can offer replacements, compensating for some of the destroyed habitat. This research reveals that explosives could be comparably advantageous – the proliferation of marine organisms on those in the Bay of Lübeck is expected to be repeated in other locations.

Between 1946 and the post-war period, 1.6m tonnes of arms were dumped off the Germany's coast. Countless of people transported them in barges; some were dropped in specific sites, the remainder just discarded at sea en route. This is the first time experts have documented how marine life has responded.

Worldwide Examples of Marine Transformation

• In the United States, retired oil and gas structures have turned into reef ecosystems
• Shipwrecks from the World War I have become environments for wildlife along the Potomac in the state of Maryland
• Tank tracks that have become habitat to reef-building organisms off Asan in the Pacific island

These locations become even more valuable for wildlife as the oceans are increasingly stripped by commercial fishing, bottom trawling and anchoring. Shipwrecks and munitions areas practically function as sanctuaries – they are not official reserves, but virtually any kind of anthropogenic disturbance is banned, explains Vedenin. As a result a numerous of marine species that are usually scarce or declining, such as the Baltic cod, are prospering.

Future Considerations

Wherever armed conflict has occurred in the recent history, adjacent waters are typically strewn with explosives, explains Vedenin. Many millions of tonnes of explosive material lie in our oceans.

The sites of these munitions are insufficiently documented, partially because of national borders, secret military information and the situation that records are buried in historic archives. They present an explosion and security hazard, as well as risk from the continuous release of poisonous compounds.

As the German government and other countries begin extracting these relics, scientists plan to safeguard the habitats that have formed nearby. In the Lübeck Bay munitions are currently being cleared.

Researchers recommend substitute these metal carcasses remaining from munitions with certain less dangerous, some non-dangerous materials, like possibly man-made habitats, says Vedenin.

He presently hopes that what transpires in Lübeck creates a example for substituting structures after weapon clearance in different areas – because also the most harmful explosives can become framework for new life.