Scallops and British bryozoa: a prime location?
What is a bryozoan?
Bryozoans, or moss animals, are a little known group of microscopic, filter feeding aquatic invertebrates. We know they have been around since at least the Ordovician Period (470 million years ago). Both living and fossil bryozoans can be found in the British Isles.
Bryozoans are important because they are:
• Foulers. Bryozoans can affect the performance or function of human-made structures such as oil rigs, buoys, moorings, ship hulls and intake pipes for power stations.
• Invasive. Bryozoans have the potential to become invasive species. They can be transported on the hulls of boats, in ships’ ballast water and by rafting on other animals, drifting seaweed or flotsam.
• Environmental indicators. Bryozoans are made of calcium carbonate, so, like corals, they are affected by ocean acidification and global temperature changes.
• Hosts of fish parasites. Several freshwater bryozoans act as intermediate hosts for myxozoans (microscopic endoparasites of freshwater fish). Myxozoans can cause proliferative kidney disease in salmon.
• Medically significant. The anti-tumour agents bryostatins were first isolated from the bryozoan Bugula neritina in 1969. Recently it has been found that bryostatins are produced by symbiotic bacteria living on the bryozoan. Conversely, the bryozoan Alcyonidium diaphanum can cause an allergic dermatitis called Dogger Bank itch, resulting in large and painful weeping blisters.
Did you know?
In New Zealand some buildings are made out of Oamaru stone, which is 99 per cent bryozoa skeletons.