G. Joan Holt 

Professor, Department of Marine Science  Associate Director for Mariculture,  Marine Science Institute  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)  Home page

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. 

Research Interests

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) larval fish transport and settlement to estuarine nursery grounds, 2) nutrition and feeding dynamics of fish larvae, 3) influence of salinity on reproduction, egg and larva fish survival in spotted seatrout, 4) reproduction and larval development of coral-reef fish and shrimp, and 5) cobia (ling) spawning and nutritional requirements for larval culture. 

Selected Publications

Holt, G.J.  2002.  Human Impacts.  In: Fishery science: the unique contributions of early life stages.  L.A. Fuiman and R.G. Werner (eds.), pp. 222-242.  Blackwell Science.

Herzka, S.Z., S.A. Holt, and G.J. Holt.  2002.  Characterization of settlement patterns of red drum (Sciaenops ocellatus) larvae to estuarine nursery habitats: a stable isotope approach.  Marine Ecology Progress Series 226:143-156.

Holt, G.J. and C.M. Riley.  2001.  Laboratory spawning of coral reef fishes: effects of temperature and photoperiod. 28th U.S.-Japan Natural Resources Aquaculture Panel: Spawning and Maturation of Aquaculture Species.  UJNR Technical Report No. 28:33-38.

Herzka, S.Z., G.J. Holt, and S.A. Holt.  2001.  Documenting the settlement history of individual fish larvae using stable isotope ratios: model development and validation. Journal of Experimental Marine Biology and Ecology 265:49-74.

Holt, G.J., and S.A. Holt. 2000. Vertical distribution and the role of physical processes in the feeding dynamics of two larval sciaenids Sciaenops ocellatus and Cynoscion nebulosus. Marine Ecology Progress Series 193:181-190. 

Lazo, J.P., G.J. Holt, and C.R. Arnold.  2000.  Ontogeny of pancreatic enzymes in larval red drum Sciaenops ocellatus.  Aquaculture Nutrition 6(3):183-192. 

Holt, G.J., and C.M. Riley. 1999. Larval and juvenile development of the cubbyu Pareques umbrosus with notes on the high hat Pareques acuminatus larvae. Bulletin of Marine Science 65(3): 825-833.