McGrail, S., 2004, Boats of the World: from Stone Age to Medieval Times. Oxford.McGrail, S., Blue, L., Kentley, E., and Palmer, C., 2003, Boats of South Asia. London.Pedersen, R. K., 2010, A Clench-Fastened Boat in Kerala, India, IJNA 39.1, 110–15.Pfaffenberger, B., 1992, Social Anthropology of Technology, Annual Review of Anthropology 21, 491–516.Ransley, J., 2009, The Backwater Boats of Kerala: Identity, Place and the World of Munruthuruthu, unpublished PhD thesis,

University of Southampton.Thomas, J., 2007, The trouble with material culture, Journal of Iberian Archaeology 9/10, 11–24.Tomalin, V., Selvakumar, V., Nair, M., and Gopi, P., 2004, The Thaikkal-Kadakkarappally Boat: an archaeological example

of medieval shipbuilding in the Western Indian Ocean, IJNA 33.2, 253–63.

Shipworm Invading the Baltic?

Attacks by the wood-boring Teredo navalis areon the increase in the Baltic, posing a threat tothe underwater cultural heritage. On the

bottom of the Baltic lie up to 100,000 extraordinarily-well-preserved wooden shipwrecks. Some have evenbeen discovered upright on the bottom with masts andrigging still standing, as if set in amber.

The Baltic Sea is one of the very few areas in theworld where sunken historic ships are still very muchintact and accessible for research. Well-preserved ship-wrecks have links not only to the countries around theBaltic, but also to many other maritime nations inEurope such as the Netherlands and the UK. Thesewrecks have so far been protected from the predationsof the shipworm because of the Baltic’s low salinity,but now it seems Teredo is spreading into the area,probably as a result of climate change. The threat to anunparalleled submerged cultural heritage is very real,and the destruction can be swift (Figs 1 and 2), some-times counted in months rather than years (woodenshipwrecks are also attacked by other organisms, suchas fungi and bacteria, but they are slower-acting andless destructive). To learn more about what is going on

and what can be done about it, the European Commis-sion has funded a research programme, ‘WreckProtect’. It started work in summer 2009 and is due tolast two years. The need is for the threatened sites to beidentified and methods of protecting them investigated.

The strategy is to provide the archaeologists, conser-vators and museums responsible for the preservation ofthe underwater cultural heritage with tools to predictthe spread of shipworm, and cost-effective methods forprotecting sites under threat. Marine archaeologists,biologists, conservators, wood-scientists and GISexperts are involved, from Sweden, Denmark, Finland,The Netherlands, France and Germany. The overallco-ordinator is Charlotte Gjelstrup Björdal of the Tech-nical Research Institute of Sweden, supported by fiveproject partners, senior researchers David Gregory ofthe Danish National Museum and Zyad Al Hamdani ofthe Geological Survey of Denmark and Greenland(GEUS), Museum Inspector Jørgen Dencker of theViking Ship Museum, Martijn Manders of the DutchCultural Heritage Agency, and Jon Havenhand andChristin Appelqvist from the University of Gothen-burg. There is also an advisory board drawn fromscientists from France, Germany and Finland. Moreinformation can be found on the project’s home pagehttp://www.wreckprotect.eu.

David GregoryDept of Conservation, National Museum of Denmark,I.C. Modewegs Vej, Brede, Kongens Lyngby, DK2800

Figure 1. Shipworm attack of sound wood exposed 3months in a marine saline environment. The upper photoshowing the outside and the lower the inside of the samepiece of wood after sectioning. (David Gregory)

Figure 2. Cross-section of a frame from a medieval wreckshowing attack by shipworm. (David Gregory)

NOTES

© 2010 The Authors. Journal Compilation © 2010 The Nautical Archaeology Society 431