LABORATORY CULTURE OF 



MARINE FISH LARVAE 



AND THEIR ROLE IN 



MARINE ENVIRONMENTAL RESEARCH 



E.D. Houde and A. K. Taniguchi 



Rosenstiel School of Marine 



and Atmospheric Science 



University of Miami 



Miami, Florida 



ABSTRACT 



The capability to predictably culture marine fish larvae beyond embryonic 

 and yolk-sac stages has been developed during the past 1 5 years. This has led to 

 advances in our understanding of how environmental variables affect survival 

 and eventual recruitment of fishes. Most marine fish larvae are planktonic 

 carnivores and consume living prey less than 150 jJtm in breadth when they first 

 feed. The most important advance in culture technology was the determination 

 of kinds and concentrations of prey that enable larvae to survive and grow at 

 predictable rates, permitting ecological, physiological, and behavioral research 

 to be undertaken. Prey concentrations necessary for growth and survival of 

 some typical marine teleost larvae, usually range from 10 to 10 per Uter. 

 Best survival rates, fastest grov/th, and lowest variabihty, have been obtained at 

 the 10 per liter concentration. Growth efficiencies and food consumption by 

 marine fish larvae are comparable to other predatory zooplankton. Some 

 knowledge about effects of predation on marine fish larvae survival has been 

 obtained, but further study is necessary, especially to determine how 

 environmental factors modify predator effects. Some areas of environmental 

 research, using cultured marine fish larvae, are reviewed. These include the 

 roles of physical and chemical variables, other than man-induced environmental 

 perturbations, and some effects of environmental change caused by man's 

 encroachment upon and alteration of marine habitats. Other important 

 advances include development of field bioassay methods to determine if 

 plankton standing stock can support fish larvae; development of biochemical 

 and histological techniques to evaluate larval condition; and the recent 

 discovery that larvae can be accurately aged using daily otoHth increments. 

 Some ideas for productive future research are proposed. 



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