Nazi Bombs, Torpedoes and Mines: The Way Ocean Creatures Thrives on Abandoned Weapons

In the slightly salty waters off the German coast rests a collection of World War II explosives, torpedoes and mines. Discarded from vessels at the end of the second world war and forgotten about, countless munitions have fused into clusters over the years. They comprise a decaying blanket on the shallow, muddy ocean floor of the Lübeck Bay in the western tip of the Baltic.

Over the decades, the explosive stockpile was overlooked and neglected. A increasing amount of visitors traveled to the sandy beaches and tranquil sea for water sports, kiteboarding and entertainment venues. Below the waves, the weapons deteriorated.

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

When the first scientists went looking to see what they were doing to the ecosystem, researchers expected to see a lifeless zone, with nothing living there because it was all toxic, states a scientist.

What they found surprised them. Vedenin recounts his colleagues shouting with surprise when the submersible first sent the images back. This was a remarkable experience, he says.

Countless of marine animals had made their homes among the munitions, creating a regenerated ecosystem denser than the ocean bottom surrounding it.

This marine city was testament to the persistence of life. Indeed astonishing how much marine organisms we discover in areas that are considered hazardous and harmful, he says.

More than 40 starfish had gathered on to one accessible fragment of explosive material. They were living on iron containers, fuse pockets and transport cases just centimetres from its dangerous content. Marine fish, crabs, sea anemones and bivalves 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 inhabiting the area, says Vedenin.

Unexpected Creature Concentration

An mean of more than 40,000 animals were residing on every meter squared of the munitions, scientists reported in their research on the finding. The nearby seabed was much less diverse, with only 8,000 creatures on every meter squared.

It is surprising that items that are meant to eliminate all life are attracting so much life, states Vedenin. One can observe how the natural world adapts after a major disaster such as the World War II and how, in certain respects, life returns to the most risky locations.

Man-made Features as Ocean Environments

Artificial constructions such as shipwrecks, offshore windfarms, oil rigs and undersea pipes can create replacements, restoring some of the removed habitat. This investigation shows that explosives could be equally beneficial – the bloom of marine organisms on those in the Bay of Lübeck is probable to be duplicated in other locations.

Between the late 1940s and the post-war period, 1.6m tons of munitions were dumped off the Germany's coast. Numerous of individuals loaded them in boats; some were placed in allocated locations, the remainder just discarded at sea during transport. This is the initial instance experts have recorded how ocean organisms has reacted.

Worldwide Examples of Ocean Transformation

• In the US, decommissioned oil and gas structures have become coral reefs
• Submerged vessels from the World War I have become habitats for marine life along the Potomac River in the state of Maryland
• Military vehicle parts that have become habitat to reef-building organisms off Asan beach in the Pacific island

These locations become even more valuable for organisms as the oceans are increasingly denuded by commercial fishing, seafloor dredging and boat mooring. Shipwrecks and munitions areas effectively act as sanctuaries – they are not official reserves, but virtually any kind of anthropogenic disturbance is restricted, states Vedenin. Consequently a many of species that are usually uncommon or diminishing, such as the Baltic cod, are thriving.

Coming Issues

Anywhere armed conflict has happened in the recent history, surrounding seas are typically containing weapons, states Vedenin. Millions of tons of volatile compounds remain in our oceans.

The locations of these weapons are poorly documented, partially because of international boundaries, restricted military information and the fact that archives are stored in historical records. They present an explosion and security hazard, as well as danger from the continuous leakage of toxic chemicals.

As the German government and additional nations begin clearing these remains, experts plan to preserve the marine communities that have formed nearby. In the Lübeck Bay explosives are currently being extracted.

Researchers recommend replace these iron structures remaining from munitions with some more secure, some safe structures, like perhaps concrete structures, suggests Vedenin.

He now hopes that what happens in Lübeck creates a precedent for substituting structures after explosive extraction in different areas – because also the most damaging explosives can become framework for marine organisms.