14 January 2000

University of Queensland PhD student Ulrike Siebeck has won a doctoral fellowship to study fish off Lizard Island.

The third-year student with the Vision, Touch and Hearing Research Centre is the 2000 Lizard Island Doctoral Fellowship winner enabling her to study and videotape the behavioural use of ultra-violet light in Damsel Fish inhabiting the Island's lagoon.

The Fellowship, worth $6000, allows Ms Siebeck access to the Lizard Island Research Station's extensive facilities including laboratories and aquaria.

"The Lizard Island Lagoon is very sheltered, allowing video and other equipment to be set up and left in place for long periods," Ms Siebeck said.

Both the Fellowship and the Research Station are administered by the Australian Museum.

Ms Siebeck spent the 1999 Northern Hemisphere summer analysing the vision abilities of hundreds of coral reef and deep sea fish. This first phase of her PhD concerned the ability of fish eyes to detect an extra colour located in the ultra-violet spectrum. "Invisible to human eyes, it's hard to imagine what seeing this colour would be like. What is more, the colour may blend with other primary colours to form a myriad of new colours, just as we mix red, green and blue light to form a rainbow of hues," Ms Siebeck said.

"The field work on Lizard Island will contribute to the second part of the PhD on fish behaviour and UV visual ability."

Supervised by the Centre's QEII research fellow, Dr Justin Marshall, Ms Siebeck's thesis explores the reasons why some fish have the ability to see the extra colour. "Of the 300 fish species I have analysed from the Great Barrier Reef and the additional 100 from my trip to Florida, I have found roughly one-third with this ability," she said.

"UV is a hot topic with fears of the damage this form of light does to coral reefs. We are interested in what good it does, how many fish use UV colouration in their daily lives. We believe they use it to help them select mates and find food. It is especially prevalent in fish who eat plankton. We believe the colour may allow these fish to more readily see the tiny particles in the ocean."

German-born Ms Siebeck said she first became fascinated with marine life at age 10 when she visited the Australian Marine Institute in Townsville with her father. She studied one year of marine biology at The University of Queensland in 1994-95 as part of an exchange arrangement with Tubingen University in south-west Germany.

For more information, contact Ulrike Siebeck (telephone 07 3365 1617).