Humans have been seafarers for millennia. Some think the first successful ocean voyage took place more than 50,000years ago.
Since humans have been putting boats into the ocean, it’s likely that some of those vessels have been lost to the waters below. There may be as many as three million wrecks littering the seabed, according to UNESCO.
Some sink by accident – during wars or rough seas – while others are sent to the seafloor on purpose: a process known as scuttling.
- In 1941, a massive WWII ship sank off the coast of Albania. Divers just went down there – and found a rare mammal living among the wreck
- Sunken warships fill this eerie lagoon – and they're scattered with gas masks, skulls and bullet casings
Although it might seem counterintuitive to dump ships at the bottom of the sea, there can be benefits. When done right, they become artificial reefs and can provide a home for many different animals.
Making an artificial reef isn’t as simple as plonking a decommissioned ship into the ocean. There’s lots of planning and preparation that must be done, such as removing any harmful substances such as asbestos, fuel, paint and wiring, and sorting permits to sink the boat in the chosen location.
The process of scuttling is carefully controlled. Strategically placed holes are typically cut into the vessel so it sinks evenly when it floods and ends up in exactly the right place on the seabed. (Obviously, the full process is more complex than this but we don’t have all day!).
At first, they are little more than bare surfaces in the ocean’s vast expanse,” writes the Department of the Environment, Tourism, Science and Innovation (DETSI), Queensland on its website.
- This giant ship sank off the Egyptian coast in 1941. Now an animal that looks like a crocodile hides in its shadows
- 10 incredible, dramatic shipwrecks around the world that are just teeming with marine life
After some time, marine life starts to encroach on the sunken structure. “They are colonised by pioneering organisms: algae, bacteria, and tiny invertebrates,” says DETSI. “These early settlers form a living skin that attracts larger organisms. Sponges soften hard edges, corals begin their slow construction, and fish find shelter in the growing complexity.”
Eventually, the reef is unrecognisable. There’s little to no sign of metal among the anemones, fish, barnacles, crustaceans, eels and more that have taken up residence.
The abundance of fish, turtles and even sharks can also benefit coastal communities nearby through food from fisheries and livelihoods that are supported by marine tourism.
Wreck diving is a very popular sport. There’s even a Shipwreck Trail in the Florida Keys.
The experience of diving on a shipwreck can be breathtaking. I’ve been followed by a free-swimming moray eel around the perimeter of the Thistlegorm in Egypt, posed for a photo in the upper deck swimming pool of the Bianca C luxury liner in Grenada and watched green turtles flit by at the Liberty wreck in Tulamben, Bali.
Shipwrecks aren’t the only things that can become artificial reefs. Army tanks, subway cars and seaplanes have all been put into the ocean to create new habitats.
- When this WWII seaplane was discovered by a fisherman in 1994, dazzling animals were found hiding in the wreck
- 80 years ago, a cargo ship struck a mine and sank to the bottom of the Mediterranean Sea. Then something staggering happened
There’s even an artist who specialises in creating underwater sculpture galleries:
Jason deCaires Taylor’s first underwater sculpture park was installed off the coast of Grenada in 2006. Since then, his submerged artworks have been established in the Bahamas, Mexico, Cyprus, Norway and more.
top image: Lionfish with school of yellowstripe scad fish swimming at HTMS Kledkaeo ship wreck in the area of Phi Phi island. One of the dive sites and artificial reef underwater in Krabi, Thailand. Credit: Zephyr18/ Getty Images
More wildlife stories from around the world:
- "In the shadow of the Himalayas swims a fish that seems to have developed a taste for human flesh…" 10 most aggressive freshwater fish
- It has superpowers, the fastest punch in the animal kingdom and and is very reluctant to leave its fortress burrow beneath the ocean floor
- "She may eat parts of her own arms to essentially accelerate her own demise." 8 females with the worst, most horrible, lives ever
