American-born, U.K.-based marine scientist, oceanographer, author and historical researcher David Mearns is also one of the world’s most experienced and successful hunters of deep-ocean shipwrecks. In his new book, The Shipwreck Hunter: A Lifetime of Extraordinary Discoveries on the Ocean Floor (2018), he charts the course of the quarter-century career that has led to the discovery of more than 20 major shipwrecks, including the British battlecruiser Hood and Australian light cruiser Sydney (both sunk during World War II) and the early 16th century Portuguese East Indiaman Esmeralda. His company Blue Water Recoveries has chalked up three Guinness World Records, and he was a key member of a team led by Microsoft co-founder Paul Allen that located and filmed the World War II Japanese battleship Musashi in 2015.
Why is it important to locate and examine historic wrecks?
Shipwrecks are an important part of our history and cultural heritage. They are reminders of what life was like in the past, and they generally describe extraordinary and tragic events. The stories told by shipwrecks educate new generations and help in commemorating the lives of people lost.
How do you research ships you intend to find?
I rely heavily on public and private archives and libraries like the U.S. National Archives. Newspapers and books are helpful, but I primarily focus on the primary source accounts created by eyewitnesses to a sinking event. They almost always contain the most credible and accurate pieces of information.
What is the most interesting part of the process for you?
The historical research is the most interesting part, as this is when you learn about the history of a ship, the people on board and what caused the loss. It is also interesting when you can locate survivors or descendants, because then you hear people’s personal stories and anecdotes. In order for people to care about a shipwreck, they need to connect with the human dimension that comes from these stories.
What is the biggest challenge?
Finding and filming a shipwreck in thousands of meters of water is extremely challenging, but raising the money to pay for such expensive expeditions is arguably more challenging. It is impossible to make a financial case to find every shipwreck, so you need to choose the ones with the most compelling stories—balanced against the funds required and the confidence you have that the wreck can be found.
How do you fund your searches for military shipwrecks, given the lack of treasure?
It requires a lot of creativity. In the past television companies, foreign governments and philanthropists have funded me. Solving mysteries or commemorating anniversaries are often used as reasons for finding wrecks.
What technologies are most important in your searches?
Many technologies are used, but the most essential are those that actually detect shipwrecks. I generally use side-scanning sonars, but wrecks can be found using magnetometers, multibeam echosounders, human divers and drones, and even satellites have been used in special cases to pinpoint wrecks in coastal waters. My job is to choose the right approach for each shipwreck.
Which emerging technologies are you excited about?
Autonomous underwater vehicle (AUV) technology has fundamentally changed the way we work, as the sonars we use to find wrecks are no longer connected to the surface ship by a long tow cable. We can now envision a time when these AUVs will either swim out from the coast under their own power or be delivered to a work site far offshore by an autonomous surface vehicle (ASV). The combined use of AUVs and ASVs will at some point eliminate the need for sending ships and people to sea. For those who love to work at sea this might seem a sad thing, but it is unstoppable progress that will benefit all of us.
Which is more useful—a manned submersible or a remotely operated vehicle?
Each has its advantages and disadvantages. ROVs are more commonly used because they are less costly, are greater in number and can be operated from different types of vessels. You can also run an ROV 24 hours a day for days on end, with many people viewing the video in real time, whereas a manned submersible is limited in the small number of people it can carry, and the bottom time is limited by the endurance of the batteries and the people.
Are there ethical differences between exploring a warship and a commercial vessel?
If people have died in the ships, there really shouldn’t be any ethical difference between how you treat the wrecks of a warship and a merchant vessel. Both need to be treated with a high degree of sensitivity, and great care is taken to avoid the disturbance of human remains. There are fundamental legal differences, however. Warships have sovereign immunity, which in theory should provide a greater degree of protection, although there have been recent cases in Indonesia, for example, where entire warship wrecks have been salvaged for scrap metal value.
How do you celebrate the discovery of a ship and still memorialize its lost crew?
I treat these as two separate things. Finding a wreck lost for decades or centuries is an achievement deserving celebration. Also, sometimes the precise moment of discovery is so sudden you can’t help but become ecstatic. Afterward, however, is the time to honor those lost by holding memorial services. I care a great deal about the people lost at sea and don’t feel I disrespect them at all because of the happiness I feel when their resting place is found.
Have any particular discoveries struck a chord with you?
HMS Hood, a wreck I found in 2001, is closest to my heart. That’s because I had such a close personal relationship with Ted Briggs, the last living survivor from Hood’s crew of 1,418 men. Two of the proudest moments in my life are when I was able to bring Ted on board our search vessel when we found Hood, and in 2015 when we recovered Hood’s bell, which Ted asked me to do before he passed away in 2008.
Is there an undiscovered shipwreck atop your list?
At the top of my list is Sir Ernest Shackleton’s Endurance. In fact, it has been top of my list since 2003, when I met Shackleton’s granddaughter Alexandra and received her family’s blessing to find and film the wreck, which is 3,000 meters below the ice-covered Weddell Sea in Antarctica. I was first attracted to Endurance because it is the ultimate challenge in terms of looking for a small wooden shipwreck in one of the most remote and hard to access places in the world. Since then I’ve become a student of Shackleton and a lover of the Antarctic landscape and icescape.
Would you prioritize efforts to map in detail the ocean floors?
Absolutely. We like to think we know everything about our planet, but the fact is that 71 percent of the earth is covered by water and only a tiny fraction of the seabed has been mapped in any great detail. So we literally know more about the surface of the Moon and Mars than we do about the surface of our own planet. That is a staggering level of ignorance about the seabed and oceans on which we rely entirely for life. As [marine biologist and explorer] Sylvia Earle likes to say “No water, no life. No blue, no green.” MH