Spotlight's Justin Leigh has been to discover more about why seaweed plays such a crucial role in maintaining the health of our marine habitats. Botanist Jan Ruhrmand shares this interest and accompanied Justin to Stackhouse Cove in west Corwnall.
Foreign species of seaweed are invading the South West coastline and threatening to take over native plants according to scientists. If these are allowed to dominate, there's a risk the marine food chain could be seriously impacted.
Cornwall's warm coastal waters are influenced by the Gulf stream; the extensive rocky reefs provide the perfect sanctuary for seaweed.
Stackhouse Cove in west Cornwall is famed for containing the widest range of seaweed species ever recorded in Britain. It was the subject of extensive research by marine biologist John Stackhouse in the 18th Century.
Listen to Justin's audio diary from his visit to Stackhouse Cove:
Jan explained that back in 1775 Stackhouse had Acton Castle built and named it after his wife Lady Susannah Acton, a wealthy heiress from Shropshire.
It is believed the sea-air and the seaweed itself had healing properties for Susannah who suffered poor health. He even had a special bath chipped out down here in the rocks so that she could bathe in the healing water and weeds.
Seaweed in west Cornwall
Stackhouse carried out experiments by trying to grow seaweeds on pebbles.
The cove near Mounts Bay is known to contain the widest range of seaweed species ever recorded in Britain.
Stackhouse had some of his findings published in a book Nereis Brittanica, or 'A Botanical Description of the British Marine Plants in Latin and English, Accompanied with Drawings from Nature'. It came out in London during 1795.
Today's Marine Biologists say there are signs that native species are declining and foreign weeds are taking over the shoreline.
Stackhouse Cove in west Cornwall
Doug Herdson from the Plymouth Marine Aquarium says lots of foreign seaweeds are turning up and displacing the British ones, because the natural predators don't recognise them so don't eat them.
Seaweed continues to have huge industrial importance. It can be found in many of the foods we eat, as the sodium alganeate is used in emulsifiers.
Some foreign species turn up here because they're carried on the hulls of ships or in the ballast water in the tanks which get flushed out in our ports.
last updated: 12/08/2008 at 11:07