Nazi Explosives, Torpedo Heads and Naval Mines: How Ocean Creatures Prosper on Discarded Weapons

In the brackish waters off the German shoreline sits a collection of World War II explosives, torpedoes and mines. Discarded from vessels at the end of the second world war and neglected, numerous explosives have accumulated over the years. They comprise a corroding layer on the shallow, muddy seafloor of the Bay of Lübeck in the western tip of the Baltic.

Over the years, the Nazi arsenal was ignored and neglected. A growing number of visitors came to the coastal areas and tranquil sea for jetskiing, kite surfing and amusement parks. Underwater, the weapons deteriorated.

Researchers expected to see a barren area, with no life because it was all poisoned, says the lead researcher.

When the first scientists went searching to see what they were doing to the marine environment, researchers anticipated finding a desert, with nothing living there because it was all contaminated, states Andrey Vedenin.

What they found surprised them. Vedenin recounts his colleagues reacting with shock when the underwater vehicle first relayed pictures. It was a great moment, he notes.

Thousands of ocean life had established habitats among the explosives, developing a renewed marine community denser than the sea floor surrounding it.

This underwater metropolis was proof to the tenacity of life. Truly astonishing how much marine organisms we discover in locations that are considered toxic and harmful, he explains.

In excess of 40 sea stars had gathered on to one accessible fragment of explosive material. They were dwelling on iron containers, ignition chambers and carrying containers just centimetres from its explosive filling. Marine fish, crabs, anemones and mussels were all discovered on the discarded explosives. It resembles a reef ecosystem in terms of the quantity of fauna that was there, notes Vedenin.

Surprising Creature Concentration

An mean of more than 40,000 animals were living on every square metre of the munitions, experts documented in their research on the observation. The surrounding area was much sparser, with only 8,000 organisms on every meter squared.

It is paradoxical that objects that are meant to kill everything are drawing so much marine organisms, states Vedenin. One can observe how nature adjusts after a devastating occurrence such as the World War II and how, in certain respects, marine life returns to the most hazardous places.

Man-made Features as Ocean Environments

Artificial structures such as sunken vessels, wind turbines, oil rigs and undersea pipes can create replacements, restoring some of the destroyed habitat. This research shows that explosives could be equally beneficial – the explosion of life on those in the Lübeck Bay is likely to be duplicated in different areas.

Between the late 1940s and the post-war period, 1.6 million tonnes of munitions were dumped off the Germany's shoreline. Countless of workers transported them in vessels; some were dropped in specific areas, others just discarded at sea during transport. This is the initial instance experts have documented how marine life has adapted.

Global Instances of Marine Adaptation

• In the United States, decommissioned energy installations have turned into coral reefs
• Sunken ships from the World War I have become homes for marine life along the Potomac in Maryland
• Tank tracks that have become habitat to coral off Asan in Guam

These places become even more important for organisms as the oceans are increasingly depleted by commercial fishing, bottom trawling and anchoring. Sunken ships and explosive disposal locations practically act as refuges – they are not official reserves, but virtually any kind of human activity is restricted, states Vedenin. As a result a many of marine species that are typically rare or declining, such as the Baltic cod, are flourishing.

Future Factors

Anywhere military conflict has taken place in the last century, adjacent waters are typically littered with munitions, explains Vedenin. Millions of tonnes of volatile compounds lie in our oceans.

The sites of these munitions are inadequately documented, in part because of national borders, restricted military information and the fact that records are stored in historic archives. They present an explosion and security risk, as well as threat from the persistent emission of toxic chemicals.

As the German government and different states begin extracting these relics, experts plan to preserve the ecosystems that have developed in their vicinity. In the Bay of Lübeck munitions are currently being cleared.

It would be wise to replace these iron structures originating from munitions with some less dangerous, various safe structures, like maybe concrete structures, says Vedenin.

He currently hopes that what occurs in the Bay of Lübeck sets a model for substituting structures after weapon clearance in other locations – because also the most harmful weaponry can become framework for marine organisms.