David A. Ziemann

The Oceanic Institute, 41-202 Kalanianaole Hwy.,
Waimanalo, HI 96795 USA

Aquarium Sciences and Conservation, in press

Populations of tropical and subtropical marine ornamental fish are being depleted worldwide to supply an increasing demand in the aquarium and fresh seafood market. Overfishing and destructive harvest techniques have left ornamental populations virtually extirpated in a number of primarily underdeveloped countries. Because only small remnant populations and significantly degraded habitat remain, population recovery under the complete absence of collection will be slow, with the high potential for population loss due to natural environmental and recruitment variability. Stock enhancement, supplementing natural recruitment with hatchery produced fry, has the potential to significantly decrease population recovery times while maintaining population vigor. Stock enhancement research on Pacific threadfin has demonstrated measurable positive impacts on recreational and commercial fisheries in experimental scale releases; similar positive impacts can be expected for enhancement efforts directed toward ornamentals. The major technological barrier to ornamental enhancement, the development of appropriate culture capabilities, is being addressed in research directed to the commercial production of fish for the aquarium trade. The Oceanic Institute has begun a research project to examine the feasibility of restoring ornamental fish populations through hatchery releases. Following the selection of priority species for enhancement research, stock enhancement research focuses on population biology and ecology, habitat utilization and carrying capacity, animal health, genetics, and behavior, and economic considerations. With successful demonstration of population enhancement, resource managers will be able to use harvest controls, natural reserves and hatchery releases in an integrated resource management strategy to maintain or restore depleted ornamental fish populations.