It is important to note that a 10% change in 

 either Z or G will have potentially large effects 

 on survivorship at any temperature. 



Growth Efficiency and Ingestion 



There was no significant relationship between 

 growth efficiency and temperature (Table 5; Fig. 

 4) for 10 species where data were adequate for 

 analysis. Mean Ki, with 0.95 confidence limits, is 

 0.29 ± 0.06, a value equal to that of juvenile, 

 carnivorous fishes (Brett and Groves 1979). One 

 species, European seabass, Dicentrarchus 

 labrax, had reported Ki well above the mean. 

 Two species, winter flounder, Pseudopleuro- 

 nectes americayius, and summer flounder, 

 Paralichthys dentatus, had Ki below the mean. 

 For some species, a large range of potential Ki 

 was reported (Fig. 4), indicating that estimates 

 of growth efficiency may vary widely in relation 

 to environment, physiology, and perhaps the 

 method used to calculate it. 



Estimated weight-specific ingestion rates 

 were determined for the 10 species from the 

 relationship / = G/Ki. For these species there is 

 a good relationship between ingestion rate (/) 

 and growth rate (G) (Fig. 5). 



FISHERY BULLETIN: VOL. 87. NO. 3, 1989 



/ = 0.1203 + 2.8691 G 



0.80 



Sfc = 0.5140. 



(5) 



There was no detectable relationship between 

 ingestion and temperature for these 10 species 

 because of the highly variable gi'owth rates and 

 growth efficiencies that were reported. How- 

 ever, given the relationship between G and T 

 (Equation (1)) and the mean value for Ki, an 

 expression describing a general relationship be- 

 tween / and T for marine fish larvae was 

 derived. 



G/K, 



(-0.0036 

 yielding 



+ 0.0094 r)/0.29, 



-0.0125 + 0.0326 T. 



(6) 



Thus, to attain the expected growth rate, in- 

 gestion must increase with temperature. A 

 threefold increase in weight-specific ingestion 

 rate is required to meet the demands of expected 

 growth at 30°C compared with that needed at 

 10°C. The result demonstrates that tropical fish 

 larvae or those living at high summer tem- 

 peratures must ingest relatively large amounts 



Table 5. — Gross growth efficiencies (K,) of marine fisfi larvae from laboratory experiments. 



'Ttie highest values reported by Houde and Schekter (1981) were not included here, based on theirnote that these values were in 

 error. 



482 



