SCU student solves a mystery of the sea

A PHD student at Southern Cross University has solved one of the mysteries of the sea and provided an answer to the dwindling number of host sea anemones. In the process, Anna Scott has recorded the first scientific pictures of the spectacular mass spawning of sea anemone.

Host sea anemones are an important part of the marine ecosystem, but in recent years their stocks have fallen dramatically in some regions because of their popularity with the aquarium trade. This has threatened to upset the fragile balance of our marine environment.

Anna, of Port Macquarie, has been working at the National Marine Science Centre in Coffs Harbour under the supervision of SCU’s Associate Professor Peter Harrison (Prof. Harrison was a member of the team that discovered mass coral spawning on the Great Barrier Reef). Using information gathered during coral spawning, Anna calculated that the anemones would begin to spawn a few nights after the full moon during March.

Her calculations proved correct and after long lonely nights waiting, she saw the spectacular process of sea anemone reproduction. Some of Anna’s anemones spawned again after full moon periods in April and May.

“Host sea anemone spawning is an awesome sight and I’m so fortunate to have witnessed it,” Anna said. “There were masses of males and females spawning in synchrony, with massive amounts of eggs and sperm being released into the water for external fertilization,” she said.

Anna harvested fertilised eggs and has now bred sea anemone in tanks at the centre giving hope that they can be farmed and returned to the wild to replenish stocks, or that they can substitute for anemone currently being taken from the sea.
5 June 2003

Further Information: Chris Stewart 0418 431484