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

In the brackish sea off the Germany's coast lies a graveyard of World War II explosives, torpedo heads and naval mines. Thrown off barges at the end of the second world war and left behind, numerous explosives have fused into clusters over the decades. They create a decaying blanket on the low-depth, silty ocean floor of the Lübeck Bay in the western part of the Baltic.

Over the decades, the wartime weapons was ignored and forgotten about. A growing number of visitors traveled to the coastal areas and calm waters for water sports, kite surfing and entertainment venues. Beneath the surface, the weapons eroded.

We initially anticipated to see a desert, with no life because it was all poisoned, explains the lead researcher.

When the initial researchers went looking to see what they were affecting to the marine environment, some of us expected to see a barren area, with no life because it was all toxic, says a scientist.

What they discovered amazed them. Vedenin recounts his scientists reacting with shock when the submersible first sent the images back. This was a memorable occasion, he says.

Thousands of sea creatures had settled among the explosives, creating a regenerated ecosystem richer than the sea floor nearby.

This ocean community was evidence to the resilience of life. Indeed remarkable how much marine organisms we discover in areas that are considered hazardous and risky, he says.

In excess of 40 sea stars had gathered on to one visible fragment of TNT. They were dwelling on steel casings, ignition chambers and transport cases just centimetres from its explosive filling. Marine fish, crabs, anemones and mussels were all discovered on the discarded explosives. You could compare it with a marine reef in terms of the abundance of creatures that was there, notes Vedenin.

Surprising Population Density

An mean of more than forty thousand creatures were residing on every meter squared of the explosives, experts reported in their paper on the discovery. The surrounding area was much poorer in life, with only eight thousand individuals on every square metre.

It is paradoxical that objects that are designed to eliminate everything are attracting so much life, explains Vedenin. One can observe how the natural world evolves after a major disaster such as the second world war and how, in certain respects, marine life establishes itself to the most dangerous places.

Man-made Features as Marine Environments

Man-made constructions such as shipwrecks, offshore windfarms, drilling platforms and undersea pipes can offer substitutes, replacing some of the lost habitat. This investigation shows that weapons could be similarly beneficial – the proliferation of marine organisms on those in the Lübeck Bay is likely to be repeated in other locations.

Between 1946 and 1948, 1.6m tonnes of weapons were dumped off the Germany's coast. Thousands of workers loaded them in barges; a portion were placed in specific sites, the remainder just dumped en route. This is the first time experts have studied how ocean organisms has responded.

Global Instances of Ocean Transformation

• In the US, decommissioned energy installations have transformed into marine habitats
• Shipwrecks from the first world war have become habitats for creatures along the Potomac in Maryland
• Tank tracks that have become home to reef-building organisms off Asan beach in Guam

These areas become even more crucial for marine life as the seas are increasingly stripped by commercial fishing, seafloor dredging and anchoring. Sunken ships and explosive disposal locations essentially serve as protected areas – they are not national parks, but almost any kind of human activity is restricted, states Vedenin. Therefore a lot of species that are typically uncommon or decreasing, such as the Baltic cod, are prospering.

Coming Issues

Anywhere warfare has happened in the last century, nearby oceans are often strewn with munitions, explains Vedenin. Millions of tons of volatile compounds rest in our marine environments.

The sites of these explosives are insufficiently recorded, in part because of international boundaries, secret defense data and the situation that records are stored in historic archives. They present an explosion and security risk, as well as risk from the continuous release of toxic chemicals.

As the German government and additional nations embark on removing these remains, scientists plan to safeguard the ecosystems that have formed nearby. In the Bay of Lübeck munitions are already being removed.

It would be wise to replace these metal carcasses remaining from munitions with certain more secure, some harmless materials, like perhaps concrete structures, says Vedenin.

He presently hopes that what happens in the Bay of Lübeck sets a model for substituting structures after munitions removal in different areas – because including the most destructive explosives can become framework for marine organisms.