CULTURE AND GROWTH OF NORTHERN ANCHOVY, 

 ENGRAULIS MORDAX, LARVAE 



John R. Hunter^ 



ABSTRACT 



Culture techniques used to rear larval anchovy through metamorphosis using laboratory cultured 

 foods are described. Anchovy larvae fed dinoflagellates Gymnodinium splendens, rotifers Brachionus 

 plicatilis, harpacticoid copepods Tisbe furcata, and brine shrimp nauplii Artemia salina, completed 

 metamorphosis (35 mm) in 74 days at 16°C with a minimum survival of 12.5*^. Growth in length and 

 weight were recorded over this interval and an excellent fit to the Laird-Gompertz growth equation was 

 obtained. Growth was comparable to that on a wild plankton diet. In a starvation experiment, most of 

 the fish that completed metamorphosis withstood a starvation period of 12- 15 days, whereas those that 

 had not completed metamorphosis did not. 



Knowledge of the growth rate of northern an- 

 chovy, Engraulis mordax Girard, is essential for 

 estimating year class success or larval survival. 

 Another important element in estimating sur- 

 vival is the time fish or larvae can withstand 

 starvation. In this report I describe the growth 

 rate of larval anchovy to metamorphosis and 

 present data on the ability of newly metamor- 

 phosed juveniles to withstand starvation. Special 

 attention is also given to culture techniques be- 

 cause this is the first time northern anchovy have 

 been reared through metamorphosis entirely on 

 cultured foods. 



Kramer and Zweifel (1970) recorded the growth 

 of anchovy larvae at 17° and 22°C for periods of 

 up to 34 days. In their experiments larvae at- 

 tained an average length of 17 mm but did not 

 reach metamorphosis, which is complete at about 

 35 mm standard length. Their larvae were fed 

 wild plankton supplemented by Artemia salina 

 nauplii. In the ensuing years, rearing techniques 

 using cultured foods have gradually been de- 

 veloped: Gymnodinium splendens for 3- to 5-day- 

 old larvae (Lasker et al. 1970), and Brachionus 

 plicatilis for 5- to 20-day-old larvae (Theilacker 

 and McMaster 1971). This paper describes the use 

 of the harpacticoid copepod Tisbe furcata which 

 are the proper size food for larvae older than 20 

 days (10 mm). All previous attempts to rear 

 anchovy larvae beyond 35 days on cultured foods 

 have failed. In all attempts Artemia nauplii were 

 used after 20 days. 



'Southwest Fisheries Center La Jolla Laboratory, National 

 Marine Fisheries Service, NOAA, La Jolla, CA 92038. 



METHODS 



Five rearing experiments were done, four at 

 16°C and one at 17° to 18°C (Table 1). Eggs for all 

 experiments were obtained from a captive popu- 

 lation of anchovy which were maintained in 

 breeding condition continuously at the South- 

 west Fisheries Center La Jolla Laboratory 

 (Leong 1971). 



Rearing tanks were cylindrical, black fiber- 

 glass, 122 cm diameter, 36 cm deep, covered 

 with a transparent acrylic plastic top, and im- 

 mersed in a water bath regulated by a refrigera- 

 tion unit. Temperature was maintained near 

 16°C in all but one experiment, and the salinity 

 was 35%. Fluorescent lamps suspended directly 

 over each tank provided about 2,000 Ix at the 

 water surface. The volume of water in the tanks 

 gradually increased from an initial volume of 200 

 liters of filtered seawater to 400 liters by about 

 20 days because of additions of seawater contain- 

 ing algae and food organisms. Thereafter, the 

 volume was maintained at about 400 liters by 

 siphoning water from the bottom from time to 

 time which also cleaned the tank. 



Records were kept of the quantity of food or 

 algae added to tanks and on alternate days 16, 

 0.20-ml aliquots were taken to measure the den- 

 sity of Brachionus plicatilis, Gymnodinium 

 splendens, and Artemia salina nauplii in the 

 tanks. Concentrations of Tisbe furcata in the 

 tanks were not recorded because they were con- 

 centrated on or near the walls and bottom of the 

 tank, but records were kept of the numbers added 

 to the tank. Details regarding the feeding of 



Manuscript accepted June 1975. 



FISHERY BULLETIN: VOL. 74, NO. 1, 1976. 



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