World War II Munitions, Torpedo Heads and Mines: The Way Ocean Creatures Flourishes on Discarded Weapons

In the slightly salty waters off the Germany's coast sits a wasteland of Nazi bombs, torpedoes and naval mines. Discarded from barges at the conclusion of the second world war and forgotten about, thousands munitions have become matted together over the years. They comprise a decaying layer on the shallow, muddy seafloor of the Bay of Lübeck in the western tip of the Baltic Sea.

Over the years, the explosive stockpile was ignored and forgotten about. A growing number of visitors came to the sandy beaches and tranquil sea for water sports, kite surfing and entertainment venues. Underwater, the munitions eroded.

We initially expected to see a desert, with no organisms because it was all toxic, explains the lead researcher.

When the initial researchers went looking to see what they were doing to the ecosystem, some of us anticipated finding a desert, with no organisms because it was all poisoned, says a scientist.

What they observed amazed them. Vedenin recounts his scientists shouting with surprise when the ROV first transmitted footage. This was a remarkable experience, he says.

Thousands of ocean life had made their homes among the explosives, forming a regenerated marine community denser than the ocean bottom around it.

This underwater metropolis was testament to the persistence of marine life. Indeed surprising how much marine organisms we observe in areas that are considered dangerous and harmful, he explains.

More than 40 starfish had clustered on to one exposed fragment of explosive material. They were residing on steel casings, fuse pockets and transport cases just a short distance from its explosive filling. Fish, crabs, sea anemones and mussels were all discovered on the historic weapons. You could compare it with a marine reef in terms of the amount of fauna that was there, states Vedenin.

Remarkable Creature Concentration

An average of more than forty thousand organisms were dwelling on every square metre of the weapons, scientists documented in their study on the observation. The surrounding area was much sparser, with only 8,000 creatures on every square metre.

It is paradoxical that items that are intended to destroy everything are attracting so much life, states Vedenin. One can observe how the natural world adjusts after a major disaster such as the World War II and how, in some way, marine life finds its way to the most risky areas.

Man-made Features as Marine Environments

Man-made structures such as shipwrecks, wind turbines, drilling platforms and undersea pipes can provide alternatives, restoring some of the lost marine environment. This study demonstrates that munitions could be similarly advantageous – the bloom of marine organisms on those in the Lübeck Bay is likely to be duplicated elsewhere.

Between 1946 and the post-war period, 1.6 million tons of munitions were dumped off the Germany's coast. Thousands of people transported them in boats; some were deposited in specific locations, the remainder just thrown overboard en route. This is the first time scientists have recorded how ocean organisms has responded.

Global Examples of Marine Adaptation

• In the US, decommissioned energy installations have become coral reefs
• Shipwrecks from the World War I have become homes for marine life along the Potomac in the state of Maryland
• Tank tracks that have become environment to coral off Asan in the Pacific island

These places become even more valuable for marine life as the oceans are increasingly denuded by fishing, bottom trawling and boat mooring. Sunken ships and explosive disposal locations effectively serve as sanctuaries – they are not official reserves, but almost any kind of human activity is banned, says Vedenin. As a result a lot of species that are typically rare or decreasing, such as the Baltic cod, are flourishing.

Future Issues

Wherever warfare has happened in the recent history, adjacent waters are usually containing explosives, explains Vedenin. Millions of tons of explosive material lie in our oceans.

The sites of these weapons are insufficiently recorded, partially because of international boundaries, classified military information and the reality that documents are hidden in historic archives. They create an detonation and security hazard, as well as risk from the continuous release of poisonous compounds.

As the German government and additional nations embark on removing these remains, experts plan to preserve the habitats that have established nearby. In the Lübeck Bay explosives are currently being cleared.

It would be wise to replace these iron structures remaining from weapons with some more secure, various safe structures, like possibly artificial reefs, states Vedenin.

He now hopes that what transpires in Lübeck sets a precedent for replacing habitats after munitions removal in different areas – because even the most destructive explosives can become foundation for marine organisms.