Scientists deliberately sank a ship just to see what would grow on it

There are 3 million shipwrecks quietly lying in the oceans around the world, some of them destroyed by natural disasters and some by human factors.

These shipwrecks are like time capsules on the seafloor. When people gradually forget the past, these shipwrecks not only preserve the accidents and deaths that have happened here, derive bizarre ghost stories, but also support new life and become the new home of countless marine creatures.

Shipwrecks and fish schools in tropical waters | Tuchong Creative

War and Shipwrecks

Slapton Sands is located on the Devon coast of England, stretching for miles between the sea and the hills. Humpback whales can occasionally be seen offshore. Local ghost stories say that at dawn on April 27 every year, hundreds of dead soldiers emerge from the waves and walk across the beach .

This ghost story is based on a real tragedy.

During World War II, in the spring of 1944, the Devon coastline became a training ground for the American Allied Forces. The US military was to complete a secret exercise here in preparation for the upcoming Normandy landings. However, misfortune soon occurred. The German E-type submarine sneaked into the US fleet and blew up the US ship full of gasoline with a torpedo , leaving a sea of ​​fire and killing more than 700 Americans.

Divers and Scotland's WWII Shipwrecks | Marcus Blatchford

On June 5, 1944, when the fleet set out from Britain, weather conditions were so bad that many landing craft and tanks sank. On the next day, the Normandy landings, many tanks and planes were sunk. By June 21, more than 40 nearby American allied ships had been sunk or damaged by German mines .

Today, little remains of the Normandy landings on land, but beneath the waves, the ocean holds the remains of tanks, warships, landing craft, aircraft and artificial ports.

When the debris of history gives birth to new life

Guns, damaged boats, and even American soldiers' helmets are the first things people find on WWII wrecks. Over time, they too become submerged underwater. But they're not alone. The Normandy landings left behind a large number of artificial reefs made of war debris in the English Channel, which have become a haven for underwater creatures.

The Leopoldville sank near Cherbourg in 1944. Hundreds of giant, mushroom-shaped anemones, the size of fists, covered the ship, trapping plankton with feathery tendrils. Starfish also clung to the hull. Fish that use the reefs for cover — pollock, conger eels and sea bass — also made their home here.

Sea anemones may have been among the first organisms to colonize shipwrecks | Marcus Blatchford

When a shipwreck rests on soft sediments that originally had no hard structures, it forms structures that are elevated above the seafloor. The habitat provided by a shipwreck is in stark contrast to the surrounding seabed , providing shelter for many fish and crustaceans, and an ideal habitat for organisms such as anemones, corals, and fan worms that feed by filtering seawater. Marine borers that feed on wood can "eat into" the wooden structure of a shipwreck. In the photic zone, the shipwreck also provides a suitable substrate for algae to grow.

It is fascinating how nature can “recycle and repair” past scenes of disaster and tragedy and give them new life.

A sunken landing ship off the Devon coast during the Normandy landings. The American flag is still on its wreckage. | Marcus Blatchford

Scientists intentionally sank a ship?

In addition to marine life visible to the naked eye, studies have shown that the richness and diversity of microbial communities near shipwrecks also increase . In a 2014 paper on shipwrecks in Australia's Great Barrier Reef, Thomas Stieglitz, an adjunct professor at James Cook University, mentioned that the impact of shipwrecks on organisms can extend to several meters from the original wreck site.

Rachel Priest, a PhD student and research assistant at Newcastle University's Marine Laboratory, said that shipwrecks not only provide an "oasis" for marine life to grow, but also help protect stocks of blue carbon - carbon dioxide trapped in the oceans and along coasts. She explained that shipwrecks sit on sediments on the seafloor, preventing the sea from washing them away, while sediments are replenished as organisms thrive and die on these artificial reefs.

Studying "shipwreck ecology" can also help detect changes in biological communities relative to baseline conditions, thereby understanding the impact of climate change on coastal organisms. Scientists decided to sink a test ship to observe how marine organisms use the shipwreck as a "wasteland"!

The abandoned Scylla, a former Royal Navy frigate, off Whitsand Bay, Cornwall | Plymouth Sound Divers

The Scylla was decommissioned in 1993 and sunk in 2004 to rest on the seabed for research. It has been performing its duties on the seafloor, allowing researchers to observe changes in biota over time.

Initially, barnacles, tube worms, sea urchins, scallops and starfish flourished, followed by the wreck’s characteristic feathery anemones and a species of soft coral known as “Dead Man’s Fingers”. By 2007, brightly coloured wrasses were thriving on the reefs, and pink sea fans, common in South Devon and Cornwall, were also present on the wreck. By 2009, 263 species had called the Scylla home .

“Dead Man’s Fingers.” Dumped ashore during a storm, dead man’s fingers look like they have been soaked in water and are swollen. They come in various shades of pink, orange, white, grey or yellow. | OCEANA Carlos Minguell

"Dead man's finger" found on the beach｜lundinandlargo.blogspot.com

Colorful creatures make their home on the Scylla | Keith Hiscock

There is even a "virtual Scylla" 3D model based on the wreck, including a climate change game for universities, where players have to choose the right species from among starfish, sea urchins, barnacles and other creatures to adapt to changing temperatures.

I can’t go diving in person but I can play games｜Virtual Scylla

In addition to virtual video games, there are also physical teaching aids where you can see the marine animals that make their home on shipwrecks in British waters.

Shipwreck Habitats Teaching Materials | maritimearchaeologytrust

There are shipwrecks added to the marine environment,

Is it necessarily a good thing?

However, artificial reefs cannot replace natural reefs, not to mention that artificial marine debris can also have a negative impact on the marine ecosystem.

First, when a shipwreck lands on the seabed, it will change or even destroy existing reefs and vegetation, and may also promote invasive species . In order to maintain the center of gravity, ships will draw seawater, lake water, etc. into the cabin to become ballast water, and then travel to all parts of the world. If you are unfortunate enough to encounter a shipwreck, the marine life in this ballast water may become invasive species at the shipwreck site.

Toxic substances released from shipwrecks can also have adverse effects on marine life. It is estimated that shipwrecks around the world contain up to 20.4 million tons of oil, which is more than 500 times more oil than was released in the Exxon Valdez spill.

Paints on ships can also be dangerous. Tributyltin (TBT) is a coating used to reduce biofouling on the bottom of ships, making navigation smoother. Areas painted with TBT are naturally less likely to have biofouling, and species colonization is only seen where the paint has peeled or non-toxic paint has been used. Fortunately, the International Maritime Organization has banned the use of antifouling paints containing TBT compounds .

In short, seriously polluted shipwrecks cannot be left on the seabed and need to be salvaged in a timely manner to prevent the local marine ecosystem from becoming fragile.

“When we dive into the seabed, we share the space with those who have survived and those who have passed away. And with the power of nature, you can see the vitality brought by the shipwreck.” | Tuchong Creative

There is also controversy over where the fish that haunt the wreck come from - are they from the surrounding environment, are they simply attracted by the wreck, or are they new? There is no clear conclusion on this issue yet, but at least we know that the wreck gave birth to new life, and perhaps we can give the ghost story of Slapton Beach a hopeful ending.

By India Bourke

Compiled by: Wanwan

Edited by: Yellowtail Pollock

Title image source: Tuchong Creative

This article comes from GuokrNature (ID: GuokrNature)