Research Product

Embryonic and larval jacksmelt, Atherinopsis californiensis, and topsmelt, Atherinops affinis, were cultured in the laboratory. Larval A. californiensis were grown for 24 days at 10, 20 and 30 o/oo salinity. Survival, 80-91%, was highest at 10 o/oo salinity. Increases in standard length (SL) and wet weight were greatest for larvae cultured at 10 or 20 o/oo. Survival of larval A. affinis cultured at 10, 20 and 30 o/oo for 24 days ranged from 99-100%. Increases in SL and wet weight were greatest for larvae cultured at 20 or 30 o /oo salinity. Illustrations of day of hatch, 8-, and 24-day-old larvae are presented with morphometric descriptions for each species. Unique melanophore patterns provide a useful character for identification of these two closely related atherinid fishes which occur sympatrically in California bays and estuaries.