Seagrass Meadows
What are they?
Seagrasses are flowering plants with roots that grow on the sandy floor of marine environments. They are quite different to seaweeds, which are a type of algae. To grow, they need sunlight and a small amount of nutrients. Seagrasses are very important in the coastal environment because they are a source of food and shelter, they oxygenate the water, trap sand and recycle nutrients.
What lives there?
Seagrass meadows are full of marine life such as seed shrimps, bristle worms, sea snails, sea stars, sea urchins, sponges, anemones, sea cucumbers and oysters. Larger animals, such as fish, squid, octopus, crabs, sharks, stingrays, dolphins and sea birds also visit the meadows. In non-tropical meadows, leatherjackets, garfish and swans eat large quantities of seagrass, but most animals can only digest seagrass leaves when they have broken down. Seagrass meadows are often called nurseries because so many types of animal, including snapper, garfish and shrimp, grow up there.
Where are these habitats?
Some of the most extensive seagrass meadows in South Australia are found in Gulf St Vincent, the body of water off the Adelaide coast. The meadows, which are usually no more than 50m offshore, are well known to snorkellers, but most people are more familiar with the dead seagrass that has washed up on the beach. Eleven species of seagrass are known to occur in South Australia , covering an area of approximately 9620km². For more pictures of South Australian sea grasses click here (link to http://www.environment.sa.gov.au/coasts//pdfs/seagrasses.pdf)
Dead seagrass washed up on a beach
Click here for a Seagrass Meadows fact sheet (PDF 239kb)