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.

Adult Male Hawaiian Sergeant Damselfish (Abudefduf abdominalis)  protecting its nest.
Adult Male Hawaiian Sergeant Damselfish (Abudefduf abdominalis) protecting its nest.

A. abdominalis eggs are elliptical, adhesive, contain bright red yolk and measure 1.2 x 0.6 mm in size. The eggs hatch after 5-9 days, depending on water temperature. Features of A. abdominalis 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. A. abdominalis larvae are easy to rear on copepods but, during the postflexion stage, they are somewhat sensitive to light and water circulation changes. The A. abdominalis larval period in culture was about 20 days.

Hawaiian Sergeant Damselfish (Abudefduf abdominalis)
Hawaiian Sergeant Damselfish (Abudefduf abdominalis)

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 very worthwhile.