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Take Only Pictures, Leave At Most Bubbles? The Case for Wreck Preservation

Should artifacts be removed and recovered from shipwrecks, or should our underwater cultural heritage be left undisturbed, and if so, under what circumstances? These are the questions that Finnish CMAS instructor, and scientific diver Rupert Simon seeks to answer based on directives from UNESCO’s 2001 Convention and several governments and training agencies.



Text and photos by Rupert Simon unless noted. Header image: Anchor of Plussa in front of the maritime museum in Mariehamn, Åland, Finland.

“Underwater cultural heritage” means all traces of human existence having a cultural, historical, or archaeological character which have been partially or totally underwater, periodically or continuously, for at least 100 years…” UNESCO 2001 Convention, Art. 1 para. 1(a)

 Many years back, a fellow diver proudly showed me an amphorae (likely Roman) he had salvaged from a wreck in the Mediterranean Sea. Relatively recently, I watched a video in which a diver brings up an intact porthole from the bottom of the Baltic. Last December, I saw photos in a scuba blog that showed divers presenting their trophies—amongst them was a self-described “… avid collector of shipwreck artifacts.” These examples show that collecting artifacts from shipwrecks, which are de-facto archaeological sites of cultural heritage, is still common. I can’t help but wonder how the habit of collecting items from wrecks for personal benefit applies to the preservation goals taught throughout all main international scuba diving certification bodies. 

Uluburun wrecksite, Kas, Turkey.

As an example, Global Underwater Explorers (GUE) states on its webpage that, “Exploring, observing, and documenting the underwater environment is critical to protecting it from threats, deliberate or inadvertent, and thereby helping conserve our aquatic heritage for future generations.”

Also, the World Confederation of Underwater Activities (CMAS) demands, “Respect for Environment and Cultural Heritage,” and, “Commercial or personal interests do not justify negatively affecting the environment or the underwater cultural heritage sites.” Of course, the education and certification bodies are not responsible for the actions of the diver once certified—we are. When reminding treasure-hunters that we were asked not to touch anything while in training, a response like “There are so many and these few don’t really matter,” or “They’ve been there for such a long time, and no one really bothered to take care of them,” seems logical. However, this perception does not withstand the reality check described below. So, what’s the problem? 

The Problem

Removing artefacts interferes with archaeological research

Archaeologists and other scientists study wreck sites to gain information about the lives of our ancestors. When we remove artefacts from their contexts, some information goes with them. But, even more information is lost without the context—the exact place where the item was in relation to other artefacts or the whole site. Therefore, archaeologists document their work meticulously. On top of that, the treasure hunter may have chosen the one item that carries critical information that leads to the identification, dating or historical context of the whole site. 

A good example is the recent excavations on the Gribshunden wreck in Sweden. One of the first items recovered was the figurehead—”the monster”—which probably would be a tempting trophy. Leaving aside the cumbersome conservation required for such artifact, the identification of the wreck would have been much more difficult without it. Niklas Erikson explained the situation at the site in 2015 and, during the discussion, the experts were worried that even a careful scientific excavation using paint brushes to keep details intact would tamper with the find (see the documentary “The Ship That Changed the World,” 2021). How much worse is the impact on such a site when taking items from a wreck with a treasure hunter approach, without considering the impact on other artefacts? Divers randomly retrieving artefacts from sunken ships do interfere with the work of archaeologists, experts, and museums collecting information for the common good. 

Impact on Other Divers

Remaining gun of the cannon side wreck, Porkkala, Kirkkonummi, Finland.

Other stakeholders include fellow wreck divers. For the diver, diving on wrecks is not necessarily connected to history. It can be driven by interest in aesthetic impression, fun, adventure, or the marine life that has taken up residence in the artificial reef. Many wreck divers simply partake  just to enjoy the underwater world. As such, the age of the site is irrelevant. 

I personally like to dive a site in Finland called “Stor Träskön tykkijolla.” The site contains a large piece from the side of a Russian two-deck line ship. Divers of our club—Nousu—reportedly saw two cannon barrels on the site. Despite many searches and to my great disappointment, I found only one. We all know that time changes everything, but consciously removing items from the seabed interferes with the experiences of other sport divers . Although I was informed that the missing gun barrel has been found, it lost its original historical value as it has been removed from its context without documentation. Why not leave things in place so we all can benefit from them? 

Ship’s bell of Helge, Åland, Finland

UNESCO Underwater Heritage Convention 

In its 31st session on the second November of 2001, the General Conference of the United Nations Educational, Scientific, and Cultural Organisation acknowledged “the importance of underwater cultural heritage as an integral part of the cultural heritage of humanity and a particularly important element in the history of peoples, nations, and their relations with each other concerning their common heritage.” They signed a document known as The UNESCO Convention on the Protection of the Underwater Cultural Heritage. The scope of the Convention protects all artefacts submerged underwater for 100 years or more. The Annex of the Convention contains ethical and scientific guidelines for activities within underwater cultural heritage sites. A detailed manual accompanies these documents.

Besides that, the sunken objects “may have a private or public owner, may be a marine peril—for navigation or for the environment—or deserve to be protected or managed for other reasons, for example as artificial reefs which became ecosystems, or marine gravesites transformed into venerated places,” Prof. Mariano J. Aznar of Spain writes in a special edition of the International Council on Monuments and Sites (ICOMOS). ICOMOS is a non-governmental international organisation dedicated to the conservation of the world’s monuments and sites. 

It follows that the introduced time limit of 100 years or older as criterion for protection is arbitrary. History is happening as we speak:  Thus,  a recently sunken item or ship can contain cultural heritage value. For example, remains of World War II mark history and should be considered and protected as heritage, too. Prominent examples for underwater heritage sites are Tirpitz in Lofoten, Norway; the HMS Royal Oak in Scapa Flow, Scotland; the MS Wilhelm Gustloff, MS Goya and SS Steuben in the Baltic Sea, Poland. All names represent tragic events and losses of human lives. Collecting items from wrecks is not just bad practice but illegal

The Finnish Example

In Finland, the Finnish Antiquities Act implementing the UNESCO Cultural World Heritage Convention protects ships or other artifacts that have sunk 100 years ago or more. The Finnish Heritage Agency and the Finnish Coast Guard work together to enforce the law. The authorities prevailed in a  case involving the cargo vessel Vrouw Maria carrying goods ordered by Katharine the Great, Empress of Russia. In other cases, lawsuits are ongoing.

Anchor ring of Kronprins Gustav Adolf, Helsinki, Finland.

The Spanish Example

Spain’s interest in protecting the remains of its medieval and early modern fleet vessels has significantly increased during the last few decades. Spain has pursued—and won— several litigation cases in national and international courts. These cases indicate that underwater objects are rarely  abandoned, but rather lost and still legally owned. Removing items from such sites cannot be considered salvage but theft. The main uncertainties around remains of Spanish warships may be in cases where the vessel sank in waters no longer under Spain’s jurisdiction. When Colombia became independent, it inherited the Spanish belongings in its territory. Does this apply to the San José, nicknamed the Holy Grail of Shipwrecks, which sank in now-Colombian waters?  Is the wreck and treasure of the San José the property of Spain or Columbia? Does this really matter today? The ship sank more than 100 years ago and could as such be considered part of the world’s cultural heritage. It would be perhaps the best option that Spain and Colombia join forces and make the find available to the broad public using proper scientific approaches. The Convention suggests so.   

Looking into one of the gun barrels of Kronprins Gustav Adolf, Helsinki, Finland
Capstan of the SMS Cöln, Scapa Flow, UK

The Example of the United Kingdom 

David Cleasby, a British maritime archaeologist, told me a story of a modern anchor found by a diver near the historical wreck of the HMS Pomone, a 38-gun Frigate built in 1805 and lost in 1811 in Alum Bay, Isle of Wight. According to the Guidance from 2012—updated in 2018—by the Maritime and Coastguard Agency, part of the Marine Management Organisation, “If you intend to recover wreck material you may require a licence from the appropriate authority.” Lifting a heavy item with a crane close to an archaeological site disturbs the sediment, potentially affecting the nearby site. And, under the Ancient Monuments and Archaeological Areas Act 1979 it is “an offence to demolish, destroy, alter or repair…without scheduled monument consent…a maritime monument.” 

It would be prudent first to apply for permission to assure that the site is correctly defined and not damaged. According to the Wreck and Salvage Law, every item retrieved must be reported to the “Receiver of Wreck.” This organisation deals with modern and historical “lost and found” items such as anchors, port holes, and coins. The legal practice assumes that every item has an owner and reporting enables the organisation to return the item to the owner and assess whether the item is historically important. 

Hence, the Receiver investigates ownership of wreck items. When the item is returned to its legitimate owner, the finder is entitled to a reward. Unclaimed wreck items belong, after a year of waiting, to the Crown. The Receiver decides on behalf of the Crown whether the finder may keep the item or turn it over to the Royal authorities. So, in the UK, when you pick up an item and keep it without reporting your findings, you have stolen it from the Queen. 

Propeller shaft of Doyle, Scapa Flow, UK  

The Sustainable Future Of Wreck Diving

Is there a place for citizen science? In the preamble of the convention, the General Conference of the United Nations Educational, Scientific, and Cultural Organization expresses its believe that (emphasis added) “cooperation among States, international organizations, scientific institutions, professional organizations, archaeologists, divers, other interested parties, and the public at large is essential for the protection of underwater cultural heritage.” Asking professionals to work together with amateurs and the public at large is simple citizen science. While this approach has century-old roots, it continues to gain traction in modern society. Can this approach be used for archaeology? 

The Finnish Society for Marine Archaeology (Suomen Meriarkeologinen Seura or MAS) was founded in 1995 and promotes marine archaeological research, education, and hobby activities in Finland. MAS initiates and coordinates marine archaeological research, training, and seminars. For example, it has jointly organised the 7th International Congress of Maritime Archaeology (IKUWA7) to be held on June 6-10, 2022 in Helsinki with Helsinki University and the Finnish Heritage Agency. One of its flagships is the initiative Porkkala Wreck Park featuring dozens of 16th to 19th century historic wreck sites. The objectives are documentation, identification, and preservation of the underwater cultural heritage. Dive clubs are invited to “adopt a wreck” for monitoring of the status and maintenance of anchored mooring buoys. This collaboration of professional and amateur organisations can very well be seen as an example project where citizens are involved in science under the guidance of professionals and experts in the field. 

Anchor of Sankbåden Wreck, Porkkala, Kirkkonummi, Finland  

The Baltic Sea Heritage Rescue Project

The German Baltic Sea Nature & Heritage Protection Association documents the condition of wrecks found in the sea, accounts for existing human remains, and notes the dangers to which the wrecks are potentially exposed. These threats are usually associated with illegal trawling, which can destroy wreck sites. Hence, removing ghost nets is the first step to approaching a new site. The work is carried out by volunteers.  

Project Baseline 

This initiative of the Global Underwater Explorers (GUE) intends to mobilise divers to engage as citizens and record changes in the world’s underwater environments. The website hosts dozens of local projects. Any diver can engage with scientific, conservation, and government entities to advance the restoration and protection of natural and cultural treasures. Although it mainly concerns marine biology and ecology projects, it may serve as an example of wreck monitoring and data communication with interested parties. 

The bathtub (in German: Badewanne) of Shinkoku Maru, Truk, Micronesia. 


In the Gulf of Finland, nicknamed “Badewanne“ by the German Navy during WWII, a group of volunteer divers finds, documents, and identifies lost, forgotten, and found wrecks. The group uses scientific methods such as measuring the dimensions of the wrecked ship, photographing, videoing, and modelling using photogrammetry for documentation. The group collaborates closely with archaeologists and the Finnish Heritage Agency and produced the documentary, “Nazi Sunken Sub/U-745 Verschollen.”

Steering wheel of the Imperial Eagle, Malta.

Heritage Malta

The Maltese Government recognised the impact of diving tourism on its underwater cultural heritage items. It tasked its agency Heritage Malta to form a unit dedicated to Underwater Cultural Heritage. The organisation identified several sites that “may be accessed by divers in a controlled and managed manner.” It finds further that “the creation of new sites that can be visited by divers and through virtual reality will give added value to the diving tourism package.” With this protective management approach, Malta hopes to attract even more deep-water wreck diving tourism in the future and become a “market leader.” 


By photographing and sharing  the deep throughout the last century, ocean explorers Jacques Cousteau and Hans Hass provoked the development of diving tourism. The number of divers has grown exponentially since the 1970s, and experts estimate that seven million people  actively practice scuba diving. [Ed.note—for a detailed study see: What is the size of the scuba diving industry?] About 2,000 divers visit the wreck of the cargo ship Thistlegorm, discovered by Cousteau in the early 1950s, each month. These estimates indicate the pressure that divers place upon cultural heritage resources, and the need for resource management. More importantly, we can make a difference by adopting the three golden rules: 

“Take only photos, leave only (at most) bubbles, touch only your own equipment.”

Collaborations in projects mentioned above such as the EU wreck park, adopt a wreck, or Baseline, can increase the meaningfulness of our hobby to help us get more out of our dives. Keep diving safe, but keep it sustainable for your diving environments. If you are ready, look at the references of the previous section and engage

The author visiting a mussel bank. Photo courtesy of Erik Wurz.

Rupert Simon on a dive trip with his club Nousu, Espoo, Finland. Photo courtesy of Jussi Tapionlinna

Rupert Simon started his diving career in Belgium in 2003 under CMAS guidance and now teaches under the same flag. He completed technical diving training under CMAS, NAUI, TDI, and GUE standards. He chairs the Scientific Committee of the Finnish Divers Federation and coordinates their dive training. He is also a member of the Finnish Maritime Archaeological Society (MAS), contributes to preservation and marine archaeological work and manages the EU wreck park in Porkkala, Kirkkonummi, Finland. As a scientific diver, he’s focused on moving towards a sustainable future.


Resurrecting a Ghost: The Launch of Ghost Diving USA




By Katie McWilliams. Photos courtesy of Ghost Diving USA unless noted. Header image by Jim Babor

Ghost Diving, formerly Ghost Fishing, has officially arrived in the United States. Naming Southern California as home for the United States chapter is not an expansion to a new territory; instead, it is a warm welcome home after a long journey. 

Ghost Fishing first arrived in Southern California in the mid 2000s spearheaded by Karim and Heather Hamza. Their team, a group of volunteer technical divers, set out to improve the health and viability of the Southern California waters. The team started with the Infidel, a sunken squid fishing vessel near Catalina Island in 45 m/150 ft. They diligently worked to clean the Infidel which took almost two years. This victory was huge for their effort. Sadly, due to lack of funding, they were unable to continue other projects. Despite this hardship and some time away from their pursuit of the ghosts, Karim and Heather are back and more motivated than ever. 

Heather’s passion is deeply rooted in her mission to advocate for animals. This passion has helped her to push through and focus on advocating for the animals that are often unseen. The marine life that goes undetected but is ever threatened in our oceans. These are the animals Heather makes very certain to see. Her passion and love for them is palpable; it radiates from her like the warmth of a sunny day. It beckons you to join her cause. This is what keeps the fire alive in her heart for Ghost Diving. She knows that she can turn the collection of nets and her experiences into educational opportunities. Heather’s aspirations for Ghost Diving USA include continuing to educate others regarding the threat of abandoned and discarded fishing gear, seeking legislative solutions to the problem, and ultimately, building an informed and empowered community that takes care of our oceans.

Karim thrives in situations that require precision and accuracy. He explains that for him, this new era of Ghost Diving is providing a fresh opportunity to build a community of elite divers that share a passion for and commitment to a great cause. He has the knowledge and experience to help train and mentor divers along their path to becoming ghost divers and intends to give all he can to the process. He wants to bring to fruition teams of divers who trust not only each other but also the process, as well as high training standards and passion for the cause. As Karim described all the things that a ghost diver needs to be, one of the original team members immediately sprang to mind, Jim Babor. 

Jim recounted the arduous process that is becoming a ghost diver and being active with projects. He started with the project as a safety diver. The deep team would come up from the dive to the nets, and Jim would ascend with them through their scheduled decompression. He then progressed into his technical training and began photographing and documenting the work the divers were doing. Jim shared something that truly captures the essence of the passion needed to be a ghost diver. When asked about some of his most memorable incidents, he recounted the amazing experience of rescuing live animals by cutting them out of nets they were trapped in.. When asked what it felt like to cut an animal out of the net and watch it swim away, Jim was simply at a loss for words. We spoke on the phone and despite Jim’s reflective pause as he gathered his thoughts, it was apparent that the experience resonates with him on a deep level rooted in compassion. For Jim, the Ghost Diving USA launch brings his commitment and journey as a ghost diver full circle.  

Helping to lead Ghost Diving USA into the future is scientific coordinator Norbert Lee, Scuba instructor, marine biologist, and active technical diver. To speak to Norbert is to feel his can-do attitude and realize his aspirations are rooted in protecting and fostering the growth of the underwater world while educating the community about ocean conservation. More importantly, his strong sense of commitment to the team effort shines through everything. In asking Norbert about his journey to becoming the US chapter coordinator, he cited the significance of the mentorship he has and continues to receive. This mentorship comes from a variety of sources including Pascal van Erp, the Hamzas and Jim Babor. 

Norbert Lee’s goal is to collect data about the environmental impact of ghost nets and how their removal impacts the health and growth of a given area. By collecting this data, he is confident he can help to educate the community about the true impact of abandoned fishing gear. He does not want to stop with nets. He wants to help recover lobster pots and other fishing apparatus that continue to catch fish after being left behind. Through educating the community, he does not want to villainize or chastise commercial fishing but rather to build working, symbiotic relationships with fishermen. By working together, Norbert hopes to have the nets removed before they do irreversible damage. 

The Founding of Ghost Diving

Pascal van Erp has a commanding grasp on the issue of abandoned fishing gear. As the founder of Ghost Diving. Pascal’s passion has built a formidable and forward-thinking movement. Speaking to Pascal is a unique experience. He exudes a quiet confidence that only time and experience can build. In researching his work to prepare for his visit and subsequent presentations, it became quite apparent that Pascal is consistent in his message. The message is that Ghost Diving breathes new life into abandoned nets that can be recycled or upcycled. To reuse and upcycle the nets means to actively contribute to the health of the planet for today and more importantly, future generations. 

Next, Pascal emphasizes Ghost Diving is dangerous. He explains that the dangers are not always apparent. Instead, they lurk in the shadows cast by ghost nets. Team dynamics are not only critical but a matter of life and death. Pascal frequently mentions the significance of trust. The ability to trust teammates to maintain composure in the face of adversity. Trusting that if something goes wrong, they can and will continue to problem solve. Trusting that they can and will save your life. The team must always perform at the highest levels. It is critical that the dive is executed according to plan and that the procedure is applied with absolute fidelity. The nets do not discriminate between human life and marine life. They are not forgiving. A diver can meet an untimely fate in the grasp of a ghost net. 

Ghost Diving USA provides a unique and exciting opportunity by planting its roots here. With support from Zen Dive Co., ghost divers will have access to equipment, standard gasses and service that will meet all their needs while ensuring the quality and reliability of these resources. While funding issues had previously plagued Ghost Fishing, the Ghost Diving partnership with Healthy Seas along with other community sponsors helps to ensure the security of the critical funding that makes these projects possible. 

Launching Ghost Diving USA

Zen Dive Co. hosted a launch event for Ghost Diving USA on Thursday, April 28. The energy in the building was electric. Everyone was thrilled to network, build community, and work towards supporting Ghost Diving USA in any possible way. Karim opened the evening by describing the net diving mission that the ghost divers had gone on earlier in the day. He explained in detail that the Moody, a Wickes class destroyer, sits at approximately 45m/150 ft. Conditions at sea were challenging. Spring is a rough season in Southern California. Variable winds cause large swells, and upwellings bring up life giving nutrients. Unfortunately, both phenomena significantly reduce visibility. This dive was no exception. Karim described a thick green cloud in the shallower depths cutting visibility to 4.5–6 m/15–20 ft. This green cloud blocked out all ambient light as the ghost divers descended, and then cutting the nets only made visibility worse. Essentially, there was no ambient light, and visibility quickly became next to zero. The ghost divers were forced to rely upon the light they brought with them. Despite the challenges, the net clean-up was successful, but the work is far from done. The ghost divers will have to return to remove more net. 

Pascal made a brief presentation about the problem of ghost nets. It was incredible to experience a room full of people feeling compelled to act, and everyone looking for the way they could best support the mission. Veronika Mikos of Healthy Seas helped to drive the point home when she explained that through partnerships with organizations such as Bracenet and Aquafil, the recycling and upcycling of nets can help to significantly reduce carbon emissions. Additionally, as the ability to recycle nets and the products made from nets grows, they become sustainable and renewable. The yarn made from the nets can be processed infinitely and never loses quality. 

The most precious resource to any of these projects is manpower. Volunteers. People willing to train hard, think of the many versus the one and ultimately focus on safety. A ghost diver is a technical diver that has successfully completed a series of training workshops that help to best prepare them for what they will experience on a net retrieval dive. The workshops also serve to build team cohesion. Pascal and Karim both explain that the need to work with technical divers is not to be exclusionary. Ghost divers need to be able to handle any situation that may arise at any moment. Technical divers are trained to do exactly that. 

For recreational divers and non-divers alike, there is a place for everyone. Ghost divers cannot do what they do without support. Jim shared with me that his son, middle-school-aged at the time, used to volunteer as surface support. He and a friend would help to bring nets onto the boat and then search through them meticulously for any trapped marine life that could be released back into the ocean. Not only did his son help to raise awareness through multiple award-winning science projects, but he also became a diver crediting his experience helping with ghost nets. The Hamzas and Norbert hope to grow Ghost Diving USA to include recreational limit projects that allow for the training and participation of recreational divers. 

Ghost Diving USA is hitting the ground running. If you are looking for a way to get involved, a great place to start is to follow them on their social media pages. They are on Facebook and Instagram as Ghost Diving USA or @GhostDivingUSA. If you would like to inquire about the application process, you can reach the USA chapter via email at

You can also act right now. Learn about what abandoned fishing gear does to our oceans and talk to others about it. Through raising awareness, you can help remind people that while the surface of the ocean is beautiful, it is what is below the surface that desperately needs our help.

Photo by Sean Farkas

Additional Resources

Ghost Diving International:
Healthy Seas:
Alert Diver:Ghost Fishing by Michael Menduno. The story of Heather Hamza and her team (2014).

Katie McWilliams is an avid diver, spending every spare moment she can in the water. Currently completing her divemaster and training for her technical pass, she wants to not only further her education and ability to explore the ocean but help with the training of divers. Specifically, Katie wants to focus on spreading awareness of how we can help the health and conservation of the oceans and marine life. Outside of diving, Katie works in moderate/severe special education. She enjoys reading, exercise, off-roading, camping and spending time with her husband, family and friends. 

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