• Sweden edition
Shipworms pose risk for Baltic treasures

Shipworms pose risk for Baltic treasures

Published: 14 Jan 2010 12:39 GMT+01:00
Updated: 14 Jan 2010 12:39 GMT+01:00

“We’re quite worried about wrecks off the coast in southwest Sweden, outside of Skåne,” University of Gothenburg marine biology researcher Christin Appelqvist told The Local.

Traditionally, shipworms have avoided the Baltic Sea due to its lower salt content. The Baltic therefore holds a number of archaeological finds featuring wrecks of wooden ships and structures which would not likely have survived were it not for the mild salinity levels of Baltic waters.

According to Appelqvist and her colleagues, around 100,000 well-preserved ship wrecks are scattered across the bottom of the Baltic Sea.

But the Teredo navalis species of shipworm, one of 65 varieties found throughout the world, has recently been making its way into the Baltic Sea, having been spotted along both the Danish and German coasts in the southern Baltic.

It was also recently found in wooden supports at the Ribersborg cold bath house in Malmö, further evidence that maritime artifacts are under threat.

Known for boring tunnels up to 30 centimetres deep into all kinds of wood, the shipworm is capable of completely destroying large maritime archaeological finds within ten years.

Three varieties of shipworm have long been common to Sweden’s west coast, meaning there are no wooden shipwrecks left.

“They’ve all been eaten up,” said Appelqvist.

But the spread of Teredo navalis into Baltic waters in southern Sweden, is a relatively new phenomenon which Appelqvist and her colleagues believe may be due to warmer seas caused by climate change.

“The warmer temperatures mean that the shipworm is less stressed and can thus tolerate lower salinity,” she explained.

“The warm water also results in a longer breeding season.”

In order to help protect Sweden’s many maritime archaeological finds, the Gothenburg-based team has joined WreckProtect, an EU project designed to determine exactly which archaeological treasures are at risk.

“We just don’t know today how far Teredo navalis may spread,” said Appelqvist, although she said that it was unlikely it would spread as far north as Stockholm.

“It will primarily depend on salt content and water temperature, but those can be affected by a number of other variables.”

While waters further north in the Baltic may not be immediately threatened by Teredo navalis, Appelqvist pointed out that there are other species of shipworm which could tolerate the chilly, low-salt waters between Stockholm and the Åland islands.

“They could easily enter that part of the Baltic in the ballast water of a passing ship,” she said.

For now, however, Appelqvist and her colleagues are focusing their efforts on the waters off the coast of Skåne, using climate data and maps of known ship wrecks to determine which archaeological finds are most threatened by Teredo navalis.

In addition to trying to predict where shipworm is likely to spread in the future, the group is also exploring various methods to protect the shipwrecks include covering them with permeable geotextile fabrics and bottom sediment.

A video featuring the exploration of the wreck of the BirgerJarl, a Swedish frigate built in 1808. The wreck now lies in about 28 metres of water between Sweden and Denmark. Courtesy of WreckProtect.

Related links:

David Landes (david.landes@thelocal.se)

Don't miss...X
Left Right

Your comments about this article

14:37 January 14, 2010 by Nemesis
This is bad news.

There is so many sites in the Baltic that have to be excavated, the Swedish archeologists literally don't have the money or resources to survery them all.

Potentially this could cause a great loss of archeology from era's which we are still trying to piece together.
15:28 January 14, 2010 by Greg in Canada
Defintately bad news. I've made hundreds of dives on historic wrecks in the Great Lakes. We're fortunate that this is cold fresh water so shipworms can not survive. However, our wrecks are now being covered by zebra mussels. These are not native to the Great lakes but were introduced by foreign ships bringing them over.
06:28 November 29, 2010 by thumar
High quality Black Salt. Black salt is also known as kala namak. It is a special type of Indian mineral salt with a distinctive / sulfurous flavor. It is not interchangeable with sea salt or table salt because of it's distinct flavor. It is rich in iron.

For more details visit our website. http://www.salt.soo.co.in/indian-black-salt-kala-namak.htm

Black salt, Indian Kala Namak, Himalayan Black Salt manufacturer, exporter, india

Different ypes of salts

Sundaram Overseas Operation, India
Today's headlines
Record win at Sweden's tough island race
Photo: Jakob Edholm/ÖTILLÖ14

Record win at Sweden's tough island race

Two Swedes crushed last year's course record at the Swimrun world championship in Stockholm's archipelago on Monday. READ  

Sweden reveals Academy Award submission
Swedish director Ruben Östlund on set. Photo. TT

Sweden reveals Academy Award submission

The movie set to represent Sweden at the 2015 Academy Awards was revealed on Monday, a film that has already won awards abroad. READ  

Hidden forest drug stash leads to prosecution

Hidden forest drug stash leads to prosecution

A 53-year-old man has been prosecuted after police in western Sweden made one of their largest drug seizures in the area. READ  

Man shot dead in hunting accident
Photo: Hunter Desportes/Flickr

Man shot dead in hunting accident

UPDATED: Police in northern Sweden say a man was killed on Monday morning after what they described as a "hunting accident". READ  

Pirate Bay Swede's trial set for final stage

Pirate Bay Swede's trial set for final stage

The mother of Swedish Pirate Bay co-founder Gottfrid Svartholm Warg has told The Local about her son's "suffering" in jail ahead of the final stages of his trial. READ  

Suspected Ebola case ruled out in Sweden
Photo: Fredrik Sandberg/TT

Suspected Ebola case ruled out in Sweden

UPDATED: Officials at a Stockholm hospital reported that they had found a suspected case of the Ebola virus on Sunday night. But the case was dismissed on Monday. READ  

Murderer on the loose after breakout

Murderer on the loose after breakout

A 34-year-old man who killed a child is on the run after he broke out of a psychiatric ward in central Sweden. READ  

Skåne floods
Huge clear up underway after Skåne floods
A Malmö bus under water. Photo: Stig Åke Jönsson/TT

Huge clear up underway after Skåne floods

Flood waters subsided in the southern Sweden region of Skåne on Monday, after flash flooding saw chaos on roads and trains at the weekend. READ  

Elections 2014
Sweden's Alliance reveals full manifesto
Photo: Henrik Montgomery/TT

Sweden's Alliance reveals full manifesto

UPDATED: Leaders of the Moderate Party, the Centre Party, the Liberal Party and the Christian Democrats have announced their complete list of election promises in Stockholm's Nacka. READ  

Zlatan scores hat trick in PSG thrashing
Photo: AP

Zlatan scores hat trick in PSG thrashing

Champions Paris Saint-Germain thumped Saint-Etienne 5-0 as Bordeaux saw their 100 percent record at the start of the Ligue 1 season ended on Sunday with a 1-1 draw against Bastia. READ  

Sweden's highest peak to lose title next year
How immigration became a key election issue
Brit's life in Sweden becomes BBC radio show
People-watching August 27
Top ten false friends in Swedish
Blog updates

25 August

Hit och dit, här och där (The Swedish Teacher) »

" Hej igen! A common challenge for Swedish language students are the location adverbs hit/här, dit/där, hem/hemma etc. Some of the location adverbs come in two versions. We should use one type of location adverb when we use a verb describes where we are, and we should use the other type of location adverb when we the verb..." READ »


25 August

The Dollar Store (Blogweiser) »

"A dollar store in Sweden. Blog post: http://t.co/tNuuvcP1q0 #USD #greenbacks #sweden #sverige pic.twitter.com/RHFAYf7U1k — Joel Sherwood (@joeldsherwood) August 23, 2014 There’s a chain here in Sweden called The DollarStore. This name always stood out to me in a country where they don’t use dollars. I went there for the first time this weekend. They actually accepted greenbacks..." READ »

Roma advocate scoops Wallenberg prize
Meet the man who made a Swedish store recall its high heels for kids
Business & Money
'How I came to run my own business in Sweden'
Expert explains why Sweden's election oozes uncertainty
City plays Schindler's List theme at Nazi rally
For Stockholm Fashion Week, here's the A-Z of Swedish fashion
'Amnesiac' man avoids deportation for ten years
Princess Estelle through the years
Business & Money
Swedish city all set for six-hour workday trial
Business & Money
Five golden rules for the Swedish job hunt
Sponsored Article
Graduates: Insure your income in Sweden with AEA
People-watching August 22-24
Armed royal guards caught (very) drunk on the job
Sweden orders textbook on Roma discrimination
Violent anti-Nazi demonstrations in Malmö
A closer look at Sweden's five official minority languages
See the destruction from the southern Sweden floods
'Sweden Democrats hold the key to elections'
Swedes celebrate first day of smelly fish season
Sponsored Article
Find out what gives this Swedish school executive appeal
Sponsored Article
Introducing...Your finances in Stockholm
Sponsored Article
Introducing...Housing in Stockholm
Latest news from The Local in Austria

More news from Austria at thelocal.at

Latest news from The Local in Switzerland

More news from Switzerland at thelocal.ch

Latest news from The Local in Germany

More news from Germany at thelocal.de

Latest news from The Local in Denmark

More news from Denmark at thelocal.dk

Latest news from The Local in Spain

More news from Spain at thelocal.es

Latest news from The Local in France

More news from France at thelocal.fr

Latest news from The Local in Italy

More news from Italy at thelocal.it

Latest news from The Local in Norway

More news from Norway at thelocal.no

jobs available
Swedish Down Town Consulting & Productions
Swedish Down Town Consulting & Productions is an innovative business company which provides valuable assistance with the Swedish Authorities, Swedish language practice and general communications. Call 073-100 47 81 or visit:
PSD Media
PSD Media is marketing company that offers innovative solutions for online retailers. We provide modern solutions that help increase traffic and raise conversion. Visit our site at: