Nazi Bombs, Torpedo Heads and Naval Mines: The Way Marine Life Thrives on Abandoned Weapons

In the brackish sea off the German coast sits a collection of Nazi bombs, torpedo heads and mines. Dumped from barges at the end of the second world war and forgotten about, numerous explosives have become matted together over the decades. They comprise a decaying carpet on the shallow, silty ocean floor of the Bay of Lübeck in the western tip of the Baltic.

Over the decades, the Nazi arsenal was overlooked and forgotten about. A growing number of visitors came to the coastal areas and calm waters for water sports, kite surfing and entertainment venues. Underwater, the munitions deteriorated.

Some of us anticipated to see a barren area, with no organisms because it was all toxic, says the lead researcher.

When the first scientists went looking to see what they were affecting to the ecosystem, researchers thought they would find a barren area, with no life because it was all poisoned, states Andrey Vedenin.

What they found astonished them. Vedenin recalls his scientists shouting with surprise when the ROV first sent the images back. It was a memorable occasion, he says.

Countless of sea creatures had settled among the munitions, forming a renewed marine community more populous than the ocean bottom nearby.

This ocean community was evidence to the persistence of marine life. It is actually astonishing how much life we observe in areas that are expected to be hazardous and harmful, he explains.

More than 40 sea stars had clustered on to one exposed chunk of explosive material. They were living on iron containers, ignition chambers and transport cases just a short distance from its volatile core. Fish, crabs, sea anemones and bivalves were all observed on the old munitions. It resembles a coral reef in terms of the abundance of animal life that was there, notes Vedenin.

Remarkable Creature Concentration

An mean of more than 40,000 animals were living on every meter squared of the explosives, experts reported in their study on the finding. The surrounding area was much less diverse, 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 marine organisms, explains Vedenin. You can see how nature adjusts after a major disaster such as the second world war and how, in certain respects, marine life returns to the most dangerous areas.

Man-made Features as Marine Environments

Man-made constructions such as sunken vessels, offshore windfarms, oil rigs and pipelines can create replacements, replacing some of the destroyed marine environment. This study demonstrates that explosives could be comparably beneficial – the proliferation of marine organisms on those in the Lübeck Bay is expected to be found in different areas.

Between 1946 and 1948, 1.6 million tonnes of weapons were dumped off the Germany's shoreline. Numerous of workers loaded them in vessels; some were deposited in specific areas, the remainder just discarded at sea during transport. This is the initial instance experts have recorded how marine life has reacted.

Global Instances of Marine Transformation

• In the US, retired oil and gas structures have turned into coral reefs
• Submerged vessels from the first world war have become habitats for marine life along the Potomac in the state of Maryland
• Military vehicle parts that have become habitat to coral off Asan in Guam

These locations become even more valuable for wildlife as the oceans are increasingly stripped by commercial fishing, seafloor dredging and anchoring. Shipwrecks and explosive disposal locations practically act as refuges – they are not official reserves, but almost any kind of anthropogenic disturbance is banned, explains Vedenin. Therefore a many of marine species that are otherwise uncommon or declining, such as the cod fish, are prospering.

Coming Factors

Wherever armed conflict has occurred in the past 100 years, nearby oceans are typically strewn with munitions, explains Vedenin. Many millions of tons of volatile compounds remain in our marine environments.

The positions of these weapons are poorly recorded, in part because of national borders, classified armed forces records and the reality that records are stored in historical records. They pose an detonation and security hazard, as well as threat from the ongoing release of poisonous compounds.

As Germany and additional nations start removing these relics, researchers aim to preserve the marine communities that have established in their vicinity. In the Lübeck Bay weapons are already being extracted.

It would be wise to substitute these steel remains left from weapons with some safer, some safe objects, like possibly artificial reefs, states Vedenin.

He presently wishes that what happens in Lübeck creates a model for substituting habitats after explosive extraction elsewhere – because including the most damaging explosives can become foundation for marine organisms.