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The University of Texas
Marine Science Institute
750 Channel View Drive
Port Aransas, TX 78373
Phone: 361-749-6711

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Holt, Joan

G. Joan Holt

Professor Emeritus
Department of Marine Science

Physical, chemical and biological factors that affect the growth and survival of larval and juvenile marine fish.


Postal Address
AUSTIN, TX 78701

Ph.D., Texas A&M University (1976)
M.S., The University of Texas at Arlington (1972)
B.S., The University of Texas at Arlington (1964)

Research Interests

Larval Fish Ecology/Marine Aquaculture 

Physiological ecology of larval fish and biochemical measures of adaptation; larval fish transport and mechanism of recruitment to estuarine nursery grounds, growth and development in controlled culture; larval fish feeding and nutrition; tropical reef fish; marine aquaculture.

Many physical, chemical and biological factors can affect growth and survival of larval and juvenile marine fish. My research focuses on biological and physical factors that limit or alter larval fish growth and development. This information is critical for understanding changes in natural populations and for increasing production in aquaculture systems. Current research using this approach includes several studies designed to clarify trophic interactions of larval fish, identify ontogenic changes in nutritional requirements, and explore biochemical techniques useful for determining physiological condition.

Specific research projects include investigations of: 1) nutrition and feeding dynamics of fish larvae, 2) significance of seagrass nursery habitats for fish larvae, 3) influence of salinity on early life stages of marine fish, 4) reproduction and larval development of coral-reef fish and shrimp, and 5) spawning and optimal requirements for larviculture.

Selected Publications

Holt, G.J. 2011. Editor, Larval Fish Nutrition. Wiley-Blackwell, John Wiley & Sons, Inc. U.K. 435 pp.

Holt, G.J., K.A. Webb, and M.B. Rust. 2011. Microparticulate diets: testing and evaluating success. In: Larval Fish Nutrition. pp. 353-372, G.J. Holt (ed). Wiley-Blackwell, John Wiley & Sons, Inc. U.K.

Fines, B. And G.J. Holt. 2010. Chitinase and apparent digestibility of chitin in the digestive tract of juvenile cobia, Rachycentron canadum. Aquaculture 303:34-39.

Watson, A.M. and G. J. Holt. 2010. Energy budget of early juvenile cobia, Rachycentron canadum. J. World Aquacult. Soc. 41:224-234.

Olivotto, I., G.J. Holt and O. Carnevali. 2009. Advances in marine ornamental aquaculture: Breeding and rearing studies. In: Coral Reefs: Biology, Threats and Restoration. Pp.1-40, T.B. Davin and A.P. Brannet (eds.), Nova Science Publishers, Inc. Hauppauge, NY.