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Brenton Stacey
Public relations officer

An Avondale College lecturer's study of the secret life of a sex-changing fish has now received sponsorship from the Australian Geographic Society.

Dr Jason Morton approached the society as part of his continuing research into the social organisation of the crimson-banded wrasse. He says the sponsorship shows the research is of public interest as the society is likely to publish his findings in its Australian Geographic magazine.

Observing and filming wrasse as often as possible makes fieldwork labour intensive, says Morton, who spends five hours above water for every half hour under water. This is perhaps one of the reasons why the society is interested in his study. The others? "Generally, there's a lack of observational research on fish in temperate regions," says Morton, "and I'm studying a sex-changing, harem-forming species, which makes the study quite unique."

Morton, a lecturer in the Faculty of Science and Mathematics, spent 300 hours under water studying crimson-banded and Maori wrasse at Catherine Hill Bay and Norah Head on the Central Coast over four years. He found the fish begin life as females but become males at age four or five years. They then live in a harem of up to 10 socially ranked females with the largest, highest ranking female likely to be the one to change sex after the male dies. Promiscuity is popular with females visiting other harems to determine whether joining will improve their rank. Since May this past year, Morton has observed more than 80 female and 15 male crimson-banded wrasse. Three of the females changed sex over the summer.

Caption: Sponsorship from the Australian Geographic Society and funding from the Avondale Foundation will help keep Dr Jason Morton under water.
Credit: Ann Stafford