Bryozoans' role in the ecosystem

Educational value

• Bryozoans, or 'moss animals', are a group of aquatic animals that live in colonies composed of a few to millions of individuals. Bryozoans eat single-celled algae; and are in turn consumed by a range of consumers including sea slugs, fish, crustaceans and sea stars. Bryozoans form a structure known as a thicket, in which many other animals such as fish and sea stars take shelter, find food and raise their young.
• Bryozoans play an important role in marine ecosystems, particularly in Australian and New Zealand waters where they are large in form and numerous, in comparison with Northern Hemisphere populations. Changes to ocean acidity could affect the formation of skeletons and shells in many marine animals, including bryozoans. If bryozoans are unable to form calcium carbonate skeletons they are not able to create the structures that many animals use for food and shelter.
• Ocean acidification is the lowering of ocean pH due to increased absorption of carbon dioxide from the atmosphere. As oceans become more acidic there is less calcium carbonate available in the oceans. Calcium carbonate is required for the production of shells and skeletons.
• Associate Professor Abby Smith is a lecturer and researcher at the University of Otago, New Zealand. Abby Smith is a biogeochemist, which means she studies the interactions between chemical, geological and biological processes in the natural world. She is involved in bryozoan research, investigating the consequences of ocean acidification.

Year level

5; 6; 7; 8; 9

Topics Acidification Ecosystems Biodiversity Consumers (Food chains) Food webs