World War II Bombs, Torpedoes and Naval Mines: How Marine Life Flourishes on Discarded Armaments

In the slightly salty waters off the Germany's coast lies a graveyard of World War II explosives, torpedoes and naval mines. Thrown off boats at the conclusion of the second world war and neglected, thousands explosives have accumulated over the decades. They create a rusting layer on the shallow, silty ocean floor of the Lübeck Bay in the western part of the Baltic Sea.

Over the years, the explosive stockpile was ignored and forgotten about. A growing number of visitors flocked to the sandy beaches and tranquil sea for jetskiing, kiteboarding and entertainment venues. Underwater, the weapons decayed.

Researchers thought to see a lifeless zone, with no life because it was all poisoned, states a scientist.

When the team went investigating to see what they were affecting to the ecosystem, researchers anticipated finding a lifeless zone, with no organisms because it was all contaminated, states Andrey Vedenin.

What they observed surprised them. Vedenin recalls his colleagues reacting with shock when the underwater vehicle first sent the images back. This was a remarkable experience, he says.

Countless of marine animals had settled among the weapons, forming a regenerated habitat more populous than the ocean bottom nearby.

This ocean community was evidence to the tenacity of marine life. Indeed surprising how much life we observe in areas that are supposed to be dangerous and risky, he says.

Over 40 sea stars had piled on to one exposed fragment of explosive material. They were living on steel casings, ignition chambers and transport cases just a short distance from its explosive filling. Marine fish, crabs, sea anemones and bivalves were all discovered on the old munitions. You could compare it with a coral reef in terms of the abundance of animal life that was inhabiting the area, says Vedenin.

Unexpected Creature Concentration

An mean of more than 40,000 organisms were living on every square metre of the weapons, researchers reported in their paper on the finding. The nearby seabed was much poorer in life, with only 8,000 organisms on every meter squared.

It is surprising that objects that are meant to kill all life are hosting so much marine organisms, explains Vedenin. You can see how the natural world adjusts after a devastating occurrence such as the second world war and how, in some way, marine life establishes itself to the most dangerous places.

Man-made Structures as Marine Environments

Man-made structures such as shipwrecks, offshore windfarms, oil rigs and undersea pipes can provide alternatives, compensating for some of the lost marine environment. This study demonstrates that explosives could be equally positive – the explosion of life on those in the Bay of Lübeck is likely to be found elsewhere.

Between 1946 and the post-war period, 1.6 million tons of munitions were discarded off the German coast. Thousands of individuals loaded them in barges; some were placed in allocated sites, others just thrown overboard while traveling. This is the first time researchers have recorded how marine life has adapted.

Worldwide Examples of Ocean Transformation

• In the US, decommissioned energy installations have transformed into reef ecosystems
• Sunken ships from the World War I have become habitats for marine life along the Potomac in Maryland
• Tank tracks that have become home to reef-building organisms off Asan in Guam

These places become even more crucial for marine life as the marine environments are increasingly stripped by fishing, seafloor dredging and anchoring. Sunken ships and munitions areas practically act as protected areas – they are not official reserves, but virtually any kind of anthropogenic disturbance is restricted, explains Vedenin. Therefore a many of marine species that are otherwise rare or diminishing, such as the cod fish, are prospering.

Future Issues

Anywhere warfare has taken place in the last century, adjacent waters are usually containing weapons, explains Vedenin. Millions of tonnes of volatile compounds remain in our seas.

The locations of these explosives are insufficiently mapped, in part because of national borders, classified defense data and the situation that archives are stored in historic archives. They pose an explosion and security risk, as well as threat from the ongoing leakage of toxic chemicals.

As Germany and additional nations embark on extracting these relics, scientists plan to safeguard the habitats that have formed around them. In the Bay of Lübeck munitions are already being extracted.

Researchers recommend replace these iron structures left from munitions with some less dangerous, various harmless materials, like perhaps man-made habitats, says Vedenin.

He now wishes that what transpires in the Bay of Lübeck creates a precedent for replacing structures after explosive extraction in other locations – because including the most damaging armaments can become framework for marine organisms.