FISH STUDY HOOKS GOLD FOR RESEARCHER

26 August 2004

Dr Ashley Williams has hooked the $2000 Graeme Kelleher Prize for his recent discoveries about movements and biology of red throat emperor which are a prized fish for commercial, recreational and charter fishers on the Great Barrier Reef. His studies are critical to better manage these important reef fish.

CRC Reef researcher Dr Ashley Williams from James Cook University found that red throat emperor may move large distances across many reefs. “Such large-scale movement is rare for coral reef fish and highlights the need for us to re-assess our beliefs that all coral reef fish are sedentary and don’t move among reefs as adults. Knowledge of the movement patterns of red throat emperor is essential for understanding the dynamics of populations, assessing stocks, managing fishing and conservation of the species on the Reef.”

“I also found that red throat emperor have different spawning potential, growth rates and life spans in different regions of the Great Barrier Reef,” said Dr Williams. “This may mean that some regions are more productive and provide better food for red throat emperor, or that fishing pressure varies among regions of the Great Barrier Reef. It could also mean that populations of red throat emperor are distinct stocks. Any of these explanations has important implications for managing red throat emperor stocks. It is possible that red throat emperor may need different management regimes in different regions of the Reef to ensure that stocks are sustained.”

Dr Williams also found that red throat emperor reach maturity at a length of about 30cm. The Queensland Department of Primary Industries & Fisheries used this information when determining a new minimum legal size limit for coral reef fish. Red throat emperor now share the same minimum legal size limit of 38cm with common coral trout to ensure that they spawn at least once before being caught and also helps to simplify regulations for fishers on the Reef.

“The content and timing of the thesis made a major contribution to the arrangements introduced into legislation under the Coral Reef Finfish management plan and helped to focus research priorities on red throat emperor,” said fisheries manager Mr Mark Elmer from the Queensland Department of Primary Industries and Fisheries. “Because of Dr Williams’ research, we will be evaluating various management strategies for red throat emperor fishery in the next two years to ensure that this fishery is sustainable.”

Dr Williams’ PhD thesis entitled Spatial patterns in population biology of a large coral reef fish: what role can movement play? has won the inaugural Graeme G Kelleher Prize of $2000 which is awarded annually to recognise an outstanding PhD thesis relevant to the ecologically sustainable development of the Great Barrier Reef World Heritage Area. The prize was established in 2003 by CRC Reef Research Centre to acknowledge the contribution of Graeme G. Kelleher to the wise use of the Great Barrier Reef.

Photo opportunity: Dr Williams will be presented with his prize by Sir Sydney Schubert, Chairman of CRC Reef, at 10.15am on Friday 27 August at CRC Reef, 6 th floor, Northtown Tower, 280 Flinders St, Townsville.

For more information: Dr Ashley Williams, CRC Reef and James Cook University, 07 4781 5113, ashley.williams@jcu.edu.au

Dr Louise Goggin, CRC Reef Media Liaison, 07 4729 8404 or 0402 243116, louise.goggin@crcreef.com