The Hawaii Larval Fish Project
Larval rearing of the Hawaiian Sergeant damselfish, Abudefduf abdominalis
August 15, 2013
Family: Pomacentridae > Genus: Abudefduf > Species: A. abdominalis
Damselfishes are mostly small (2” to 4” long), brightly colored and highly territorial coral reef fishes comprising 19 genera/200 species. They occupy a variety of important ecological roles as territorial “algae farmers”, detritivores, grazers, schooling planktivores, prey for reef piscivores, and even facultative parasite pickers. Damselfishes are the most heavily traded marine fish in the aquarium trade due to their bright colors, small size and low price. However, only the clownfishes are available consistently through aquaculture due to their short and uncomplicated larval stage. Other heavily traded damselfish species (Chromis, Chrysiptera and Dascyllus sp.) are more difficult and costly to raise and very abundant in the wild, making them less desirable farming candidates.
The Hawaiian Sergeant (Abudefduf abdominalis) is a large, colorful damselfish, endemic to the Islands of Hawaii. A. abdominalis was reared from collected eggs removed from nests in waters off the west side of Oahu in August, 2012. The eggs are elliptical, adhesive, contain bright red yolk and measure 1.2 x 0.6 mm in size. They hatch after 5-9 days, depending on water temperature. Features of the larvae include the early forming dorsal spines and pelvic rays; enlarged pelvic fins; yellowish body covered with small, black spots; and sudden changes in form and pigmentation with little growth. The larvae are easy to rear on copepods but, during the postflexion stage, they are somewhat sensitive to light and water circulation changes. The larval period of A. abdominalis in culture was about 20 days. Sergeant damselfish (Abudefduf species) are inexpensive and potentially aggressive aquarium fish with limited value to the aquarium trade. However, the beauty, interesting behavior and short rearing phase of the larvae makes experimental breeding worthwhile.