Nazi Bombs, Torpedo Heads and Mines: How Marine Life Thrives on Dumped Weapons

In the slightly salty sea off the Germany's coast rests a wasteland of World War II explosives, torpedo heads and naval mines. Dumped from boats at the end of the second world war and left behind, numerous explosives have fused into clusters over the decades. They create a corroding blanket on the low-depth, muddy seafloor of the Bay of Lübeck in the western part of the Baltic Sea.

Over the years, the wartime weapons was ignored and neglected. A increasing amount of visitors came to the coastal areas and tranquil sea for jetskiing, kite surfing and amusement parks. Beneath the surface, the weapons decayed.

We initially thought to see a lifeless zone, with no organisms because it was all toxic, says a scientist.

When the initial researchers went searching to see what they were doing to the ecosystem, the team expected to see a desert, with no organisms because it was all contaminated, explains Andrey Vedenin.

What they discovered astonished them. Vedenin recalls his colleagues exclaiming in amazement when the ROV first sent the images back. That moment was a memorable occasion, he notes.

Thousands of sea creatures had established habitats among the explosives, developing a renewed marine community denser than the ocean bottom nearby.

This underwater metropolis was testament to the resilience of marine life. It is actually remarkable how much marine organisms we observe in places that are expected to be dangerous and harmful, he explains.

More than 40 sea stars had piled on to one visible piece of TNT. They were living on metal shells, fuse pockets and storage boxes just a short distance from its explosive filling. Marine fish, crustaceans, anemones and bivalves were all found on the old munitions. It resembles a coral reef in terms of the amount of animal life that was inhabiting the area, says Vedenin.

Surprising Creature Concentration

An mean of more than forty thousand organisms were residing on every meter squared of the munitions, researchers reported in their research on the finding. The nearby seabed was much poorer in life, with only eight thousand individuals on every meter squared.

It is surprising that things that are designed to eliminate all life are drawing so much marine organisms, states Vedenin. It's evident how nature evolves after a catastrophic event such as the second world war and how, in certain respects, life establishes itself to the most risky places.

Artificial Features as Ocean Environments

Artificial features such as sunken vessels, offshore windfarms, oil rigs and undersea pipes can provide replacements, compensating for some of the destroyed habitat. This research reveals that weapons could be equally positive – the bloom of marine organisms on those in the Bay of Lübeck is probable to be repeated in different areas.

Between the late 1940s and 1948, 1.6m tons of munitions were disposed of off the German coast. Thousands of workers placed them in vessels; some were placed in allocated sites, the remainder just discarded at sea during transport. This is the first time researchers have recorded how ocean organisms has responded.

Global Examples of Ocean Transformation

• In the US, retired drilling platforms have transformed into marine habitats
• Sunken ships from the World War I have become habitats for wildlife along the Potomac in Maryland
• Tank tracks that have become environment to coral off Asan in Guam

These locations become even more important for wildlife as the seas are increasingly stripped by commercial fishing, bottom trawling and anchoring. Shipwrecks and explosive disposal locations effectively function as sanctuaries – they are not national parks, but nearly any kind of anthropogenic disturbance is prohibited, states Vedenin. Consequently a lot of marine species that are otherwise rare or decreasing, such as the Baltic cod, are flourishing.

Coming Issues

Anywhere military conflict has happened in the recent history, adjacent waters are usually strewn with explosives, states Vedenin. Many millions of tons of volatile compounds remain in our seas.

The locations of these munitions are poorly mapped, in part because of international boundaries, secret armed forces records and the situation that documents are buried in historic archives. They pose an detonation and security danger, as well as risk from the continuous release of poisonous compounds.

As Germany and other countries begin clearing these remains, scientists plan to safeguard the marine communities that have established nearby. In the Lübeck Bay weapons are already being extracted.

We should substitute these steel remains originating from munitions with certain less dangerous, various safe objects, like perhaps concrete structures, states Vedenin.

He currently hopes that what transpires in Lübeck creates a precedent for substituting material after munitions removal elsewhere – because including the most damaging armaments can become foundation for new life.