Marine life thriving on World War II explosives in Baltic Sea, study finds
Researchers document crabs, worms and fish on warhead surfaces at a German weapons dump; findings challenge assumptions about pollution and biodiversity in the Baltic.
An undersea submersible has spotted crabs, worms and fish thriving on the surfaces of World War II explosives thought to be toxic to marine life in the Baltic Sea. The discovery came at a former weapons dump site, where researchers found more organisms living on warheads than on the surrounding seabed.
At the Bay of Lübeck off the coast of Germany, the team filmed networks of anemones, starfish and other life on pieces of V-1 flying bombs used by Nazi Germany. "We were prepared to see significantly lower numbers of all kinds of animals," said Andrey Vedenin of the Senckenberg Research Institute in Germany. "But it turned out the opposite."
German waters alone contain about 1.6 million tons (1.5 million metric tonnes) of dumped weapons, mostly from the two world wars in the 20th century. Dumped relics can contain nuclear and chemical remnants as well as explosives like TNT.
Why would sea creatures make their home on contaminated weapons? They could be drawn to the hard surfaces, which are in short supply in the Baltic Sea. The seafloor is mainly a flat bed of mud and sand because stones and boulders were fished out of the water for construction in the 1800s and 1900s, Vedenin said. The area is also fairly isolated from human activity because of the chemicals, creating a somewhat protective bubble for the critters to thrive despite some toxic tradeoffs.
Scientists hope to calculate how much contamination was absorbed by sea life. Another important next step is to see what happens after the critters settle and whether they are capable of reproducing, Porter said.
"Normally, one does not study the ecology of bombs," said James Porter, an ecologist at the University of Georgia who was not involved with the research. He said the work offers a glimpse into how life can adapt to polluted, man-made substrates.
Marine conservation biologist David Johnston with Duke University, who recently mapped sunken World War I ships that became habitats along the Potomac River in Maryland, called the findings a "cool testimony to the strength of life." He noted that such wrecks have become de facto habitats even as they carry a toxic tradeoff.
The study was published Thursday in the journal Communications Earth and Environment. The AP Health and Science Department's coverage notes that the research adds to a growing field of work showing wildlife thriving in polluted sites.