Nazi Bombs, Torpedoes and Mines: The Way Marine Life Thrives on Abandoned Weapons

In the slightly salty sea off the German coast sits a collection of World War II explosives, torpedoes and naval mines. Dumped from boats at the conclusion of the second world war and left behind, countless munitions have accumulated over the years. They comprise a rusting blanket on the shallow, silty seafloor of the Bay of Lübeck in the western part of the Baltic Sea.

Over the decades, the Nazi arsenal was ignored and forgotten about. A growing number of tourists traveled to the sandy beaches and calm waters for water sports, kite surfing and amusement parks. Beneath the surface, the munitions decayed.

We initially thought to see a barren area, with no life because it was all poisoned, says the lead researcher.

When the team went looking to see what they were affecting to the ecosystem, the team expected to see a desert, with no organisms because it was all poisoned, states the lead researcher.

What they observed amazed them. Vedenin recounts his team members shouting with surprise when the underwater vehicle first sent the images back. It was a remarkable experience, he says.

Thousands of marine animals had made their homes among the munitions, developing a regenerated habitat richer than the seabed nearby.

This marine city was evidence to the resilience of marine life. It is actually astonishing how much marine organisms we discover in areas that are considered hazardous and risky, he explains.

More than 40 starfish had clustered on to one visible piece of TNT. They were living on iron containers, ignition chambers and carrying containers just a short distance from its explosive filling. Marine fish, crabs, sea anemones and bivalves were all found on the old munitions. You could compare it with a coral reef in terms of the abundance of creatures that was present, states Vedenin.

Surprising Creature Concentration

An mean of more than forty thousand organisms were dwelling on every meter squared of the explosives, scientists documented in their research on the observation. The nearby seabed was much sparser, with only 8,000 organisms on every meter squared.

It is surprising that things that are intended to destroy all life are attracting so much life, states Vedenin. One can observe how the natural world adjusts after a catastrophic event such as the World War II and how, in certain respects, life establishes itself to the most hazardous locations.

Man-made Features as Ocean Environments

Man-made features such as sunken vessels, wind turbines, oil rigs and undersea pipes can offer alternatives, restoring some of the removed habitat. This study reveals that weapons could be equally positive – the proliferation of life on those in the Lübeck Bay is likely to be found in different areas.

Between the late 1940s and 1948, 1.6m tonnes of arms were discarded off the Germany's shoreline. Countless of workers placed them in barges; a portion were deposited in specific areas, others just dumped en route. This is the first time researchers have documented how ocean organisms has reacted.

Global Examples of Ocean Transformation

• In the United States, decommissioned oil and gas structures have turned into coral reefs
• Submerged vessels from the World War I have become environments for marine life along the Potomac River in Maryland
• Military vehicle parts that have become habitat to coral off Asan beach in Guam

These places become even more valuable for marine life as the seas are increasingly depleted by fishing, seafloor dredging and anchoring. Shipwrecks and weapons dump sites essentially act as refuges – they are not national parks, but virtually any kind of human activity is restricted, explains Vedenin. Therefore a lot of marine species that are typically scarce or diminishing, such as the Baltic cod, are thriving.

Coming Issues

Wherever armed conflict has happened in the last century, adjacent waters are usually containing munitions, states Vedenin. Millions of tonnes of explosive material lie in our seas.

The locations of these explosives are poorly mapped, in part because of international boundaries, secret military information and the reality that records are buried in historical records. They pose an detonation and safety hazard, as well as threat from the continuous leakage of poisonous compounds.

As the German government and additional nations begin clearing these relics, experts aim to preserve the marine communities that have established around them. In the Bay of Lübeck weapons are already being removed.

It would be wise to replace these metal carcasses left from munitions with certain safer, some harmless objects, like possibly man-made habitats, suggests Vedenin.

He now wishes that what happens in the Bay of Lübeck establishes a model for substituting structures after explosive extraction elsewhere – because including the most harmful armaments can become framework for marine organisms.