Nazi Bombs, Torpedo Heads and Mines: How Ocean Creatures Thrives on Discarded Armaments

In the brackish sea off the Germany's coast rests a collection of World War II explosives, torpedoes and naval mines. Thrown off boats at the end of the second world war and left behind, thousands explosives have accumulated over the decades. They create a decaying blanket on the shallow, muddy seafloor of the Bay of Lübeck in the western part of the Baltic.

Over the years, the wartime weapons was ignored and neglected. A increasing amount of tourists flocked to the coastal areas and tranquil sea for water sports, kiteboarding and amusement parks. Beneath the surface, the weapons eroded.

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

When the initial researchers went looking to see what they were affecting to the ecosystem, the team thought they would find a lifeless zone, with no life because it was all toxic, explains Andrey Vedenin.

What they observed surprised them. Vedenin recalls his team members reacting with shock when the submersible first sent the images back. That moment was a remarkable experience, he recalls.

Numerous of ocean life had established habitats on the weapons, creating a renewed ecosystem denser than the sea floor around it.

This ocean community was testament to the tenacity of life. Indeed remarkable how much marine organisms we observe in locations that are expected to be hazardous and harmful, he states.

Over 40 starfish had piled on to one exposed piece of TNT. They were dwelling on iron containers, detonator compartments and transport cases just a short distance from its explosive filling. Marine fish, crustaceans, sea anemones and mussels were all observed on the historic weapons. You could compare it with a reef ecosystem in terms of the amount of animal life that was present, says Vedenin.

Remarkable Population Density

An average of more than forty thousand animals were dwelling on every meter squared of the weapons, scientists reported in their research on the discovery. The nearby seabed was much less diverse, with only eight thousand individuals on every square metre.

It is ironic that things that are designed to destroy everything are hosting so much life, states Vedenin. You can see how nature evolves after a major disaster such as the World War II and how, in some way, marine life returns to the most hazardous locations.

Man-made Structures as Ocean Environments

Artificial structures such as shipwrecks, wind turbines, drilling platforms and pipelines can provide alternatives, replacing some of the destroyed marine environment. This study demonstrates that weapons could be equally positive – the proliferation of marine organisms on those in the Lübeck Bay is probable to be repeated elsewhere.

Between the late 1940s and the post-war period, 1.6m tonnes of weapons were dumped off the German coast. Numerous of workers placed them in boats; a portion were deposited in designated sites, others just discarded at sea en route. This is the first time experts have documented how marine life has adapted.

Global Instances of Marine Adaptation

• In the United States, decommissioned oil and gas structures have turned into coral reefs
• Submerged vessels from the first world war have become habitats for creatures along the Potomac in the state of Maryland
• Military vehicle parts that have become home to coral off Asan in the Pacific island

These areas become even more important for organisms as the marine environments are increasingly depleted by commercial fishing, seafloor dredging and boat mooring. Sunken ships and explosive disposal locations practically act as refuges – they are not national parks, but nearly any kind of human activity is prohibited, says Vedenin. As a result a numerous of marine species that are typically rare or declining, such as the cod fish, are flourishing.

Future Issues

Wherever armed conflict has occurred in the recent history, surrounding seas are usually strewn with munitions, says Vedenin. Many millions of tonnes of volatile compounds lie in our oceans.

The sites of these weapons are inadequately documented, partially because of international boundaries, secret defense data and the reality that archives are hidden in old files. They create an detonation and safety hazard, as well as danger from the persistent emission of poisonous compounds.

As Germany and other countries start clearing these artifacts, experts plan to protect the habitats that have formed nearby. In the Lübeck Bay explosives are already being cleared.

Researchers recommend substitute these steel remains remaining from munitions with certain less dangerous, some safe objects, like perhaps artificial reefs, states Vedenin.

He presently hopes that what occurs in Lübeck sets a example for replacing structures after explosive extraction elsewhere – because even the most harmful explosives can become foundation for ocean ecosystems.