Protecting the Marine Historic Environment: Detecting, Investigating and Reducing Heritage Crime at Sea

• In July 2014, two divers were ordered to pay more than £60,000 in fines and costs after admitting a string of offences related to the plundering of artefacts from historic wreck sites.
• In September 2015, a diver was jailed for two years for fraudulently selling three rare 17th-century cannon found in the Thames Estuary. He was ordered to pay £35,000 in costs and has been made subject to proceedings to recover monies totalling £51,000 gained from the sale of the guns.
• In May 2016, another man was found guilty of offences relating to the salvage of a shipwreck and was sentenced to a community order of 150 hours of unpaid work by a jury at Newcastle upon Tyne Crown Court.
• In January 2017, two divers were charged with stealing from HMS Hermes (a converted cruiser sunk by a German U-boat in the Dover Strait in October 1914 with the loss of 44 lives).

The majority of these offences relate to the attempt to steal metal artefacts.

It's well established that the frequency of metal theft is linked to the mean price of metals. A higher price equates to a greater number of reported thefts, and vice versa.

This seemingly holds true for underwater cultural heritage: the widespread publicity afforded to the four criminal cases noted above (and their associated deterrent effect), coupled with a general climate of declining metal prices, has resulted in a fall in the number of reported thefts from submerged archaeological sites in recent years.

One of the biggest challenges in protecting underwater cultural heritage from uncontrolled salvage and theft lies in its remoteness; by their nature, shipwrecks tend to lie in areas hazardous to shipping and in locations not frequently visited or patrolled.

In order to facilitate security on some of the most important remains of our maritime past, we have established links with the National Coastwatch Institution (NCI; a voluntary charitable organisation providing a visual watch along UK coasts) and Project Kraken (a national scheme aimed at encouraging the reporting of suspicious behaviour at sea).

We also use a developed network of affiliated volunteers, diving groups and mariners who all help in caring for our underwater heritage.

While Historic England does not have the capacity to mount patrols to monitor our marine heritage, other government departments and agencies do (such as the RN Fishery Protection Squadron and Border Force). We have therefore commissioned research to understand the full range of government marine capabilities to determine whether additional 'heritage protection' duties could be accommodated during routine patrols. This research is expected to conclude later this year.

Additionally, we've recently commissioned an innovative investigation into the provision of underwater forensic marking. This work builds on the well-established practice of marking property (for example, forensic tagging), which has led to a number of successful prosecutions. We intend to facilitate the development of a methodology for marking archaeological artefacts underwater. Used in conjunction with more traditional crime prevention measures, this will prove a very effective theft deterrent.