World War II Explosives, Torpedoes and Mines: The Way Marine Life Prosper on Discarded Weapons

In the brackish sea off the Germany's coast rests a wasteland of Nazi bombs, torpedo heads and mines. Dumped from boats at the end of the second world war and forgotten about, thousands munitions have accumulated over the decades. They comprise a corroding layer on the low-depth, silty seafloor of the Lübeck Bay in the western tip of the Baltic Sea.

Over the decades, the explosive stockpile was overlooked and neglected. A increasing amount of visitors traveled to the sandy beaches and tranquil sea for jetskiing, kiteboarding and amusement parks. Below the waves, the munitions eroded.

Some of us anticipated to see a desert, with nothing living there because it was all poisoned, says Andrey Vedenin.

When the initial researchers went searching to see what they were doing to the ecosystem, researchers thought they would find a barren area, with nothing living there because it was all toxic, states a scientist.

What they observed surprised them. Vedenin recalls his colleagues reacting with shock when the ROV first transmitted footage. It was a remarkable experience, he recalls.

Thousands of ocean life had settled amid the munitions, creating a revitalized habitat denser than the ocean bottom surrounding it.

This underwater metropolis was proof to the persistence of marine life. Truly remarkable how much marine organisms we observe in places that are considered hazardous and dangerous, he states.

Over 40 starfish had gathered on to one accessible fragment of TNT. They were residing on iron containers, ignition chambers and storage boxes just centimetres from its dangerous content. Marine fish, crustaceans, sea anemones and mussels were all found on the discarded explosives. It's similar to a coral reef in terms of the abundance of creatures that was inhabiting the area, says Vedenin.

Remarkable Creature Concentration

An mean of more than forty thousand creatures were dwelling on every square metre of the munitions, researchers wrote in their paper on the observation. The nearby seabed was much sparser, with only 8,000 creatures on every meter squared.

It is paradoxical that objects that are designed to destroy everything are drawing so much marine organisms, states Vedenin. One can observe how the natural world evolves after a catastrophic event such as the World War II and how, in some way, marine life finds its way to the most dangerous locations.

Artificial Structures as Ocean Habitats

Man-made structures such as shipwrecks, wind turbines, oil rigs and undersea pipes can offer alternatives, replacing some of the removed habitat. This study reveals that explosives could be similarly positive – the bloom of marine organisms on those in the Lübeck Bay is expected to be repeated in different areas.

Between the late 1940s and 1948, 1.6 million tonnes of munitions were dumped off the Germany's coast. Countless of workers loaded them in barges; some were dropped in specific areas, others just thrown overboard en route. This is the first time scientists have recorded how marine life has adapted.

Global Instances of Marine Adaptation

• In the United States, retired drilling platforms have become coral reefs
• Sunken ships from the first world war have become habitats for wildlife along the Potomac in the state of Maryland
• Military vehicle parts that have become environment to reef-building organisms off Asan in Guam

These areas become even more important for organisms as the marine environments are increasingly stripped by fishing, seafloor dredging and anchoring. Shipwrecks and weapons dump sites practically serve as sanctuaries – they are not national parks, but virtually any kind of human activity is banned, states Vedenin. As a result a many of marine species that are usually rare or declining, such as the Baltic cod, are thriving.

Coming Factors

Anywhere military conflict has occurred in the last century, adjacent waters are often containing munitions, explains Vedenin. Many millions of tons of explosive material lie in our marine environments.

The positions of these weapons are inadequately recorded, partially because of international boundaries, classified armed forces records and the fact that records are stored in old files. They create an detonation and security risk, as well as risk from the persistent leakage of toxic chemicals.

As the German government and additional nations embark on removing these remains, experts aim to safeguard the marine communities that have formed around them. In the Lübeck Bay weapons are already being removed.

It would be wise to substitute these iron structures left from weapons with some more secure, some safe structures, like perhaps artificial reefs, suggests Vedenin.

He currently aspires that what happens in the Bay of Lübeck creates a example for replacing habitats after munitions removal in other locations – because even the most harmful weaponry can become foundation for new life.