World War II Munitions, Torpedoes and Naval Mines: How Marine Life Prosper on Dumped Weapons

In the slightly salty sea off the German coast lies a graveyard of Nazi bombs, torpedoes and naval mines. Thrown off vessels at the conclusion of the second world war and forgotten about, countless munitions have accumulated over the years. They create a rusting layer on the low-depth, muddy seafloor of the Lübeck Bay in the western part of the Baltic Sea.

Over the decades, the wartime weapons was overlooked and neglected. A increasing amount of tourists came to the coastal areas and tranquil sea for jetskiing, kite surfing and entertainment venues. Beneath the surface, the weapons deteriorated.

Some of us expected to see a lifeless zone, with no life because it was all poisoned, says Andrey Vedenin.

When the team went looking to see what they were affecting to the marine environment, researchers expected to see a barren area, with no organisms because it was all poisoned, explains the lead researcher.

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

Countless of marine animals had settled on the explosives, creating a regenerated habitat richer than the sea floor nearby.

This underwater metropolis was evidence to the resilience of marine life. It is actually astonishing how much life we observe in places that are supposed to be dangerous and risky, he explains.

More than 40 starfish had gathered on to one exposed fragment of TNT. They were dwelling on metal shells, fuse pockets and transport cases just centimetres from its volatile core. Marine fish, crustaceans, anemones and bivalves were all discovered on the old munitions. It's similar to a coral reef in terms of the quantity of animal life that was there, says Vedenin.

Surprising Population Density

An average of more than 40,000 creatures were residing on every meter squared of the explosives, scientists documented in their paper on the finding. The nearby seabed was much poorer in life, with only 8,000 individuals on every square metre.

It is paradoxical that items that are intended to eliminate all life are hosting so much marine organisms, explains Vedenin. It's evident how the natural world evolves after a catastrophic event such as the second world war and how, in some way, life returns to the most risky areas.

Man-made Features as Ocean Habitats

Man-made features such as shipwrecks, wind turbines, oil rigs and undersea pipes can offer alternatives, replacing some of the lost habitat. This study reveals that explosives could be comparably positive – the bloom of life on those in the Lübeck Bay is probable to be repeated elsewhere.

Between the late 1940s and the post-war period, 1.6 million tonnes of arms were disposed of off the German coast. Thousands of individuals transported them in barges; some were deposited in designated areas, others just thrown overboard en route. This is the initial instance researchers have recorded how marine life has adapted.

Worldwide Examples of Ocean Transformation

• In the US, retired energy installations have transformed into reef ecosystems
• Submerged vessels from the World War I have become habitats for marine life along the Potomac in the state of Maryland
• Military vehicle parts that have become environment to coral off Asan beach in Guam

These locations become even more valuable for marine life as the oceans are increasingly depleted by fishing, bottom trawling and anchoring. Sunken ships and munitions areas essentially act as protected areas – they are not official reserves, but virtually any kind of human activity is prohibited, states Vedenin. Therefore a many of species that are typically rare or decreasing, such as the cod fish, are prospering.

Coming Factors

Wherever warfare has happened in the past 100 years, nearby oceans are often littered with munitions, says Vedenin. Many millions of tonnes of dangerous substances remain in our seas.

The positions of these munitions are inadequately documented, in part because of national borders, secret military information and the situation that documents are buried in historic archives. They present an explosion and security danger, as well as risk from the continuous leakage of toxic chemicals.

As Germany and different states begin clearing these remains, experts aim to preserve the ecosystems that have formed nearby. In the Bay of Lübeck explosives are currently being removed.

It would be wise to substitute these iron structures originating from munitions with some safer, various non-dangerous materials, like possibly man-made habitats, states Vedenin.

He presently aspires that what transpires in Lübeck sets a example for replacing material after munitions removal in different areas – because also the most harmful weaponry can become framework for marine organisms.