Current aquarium research efforts are centered on rockfish reproduction, culture and early life history, along with various other concurrent projects. Rockfishes of the genus Sebastes comprise one of the most important and heavily utilized groups of commercial and recreational fishes occurring off California. Over the last few years there has been increasing concern that certain populations and species of rockfishes are showing signs of overutilization. One of the goals of our research is to learn more about the life-history of various species of rockfish, given that much of this information is incomplete or lacking
Areas of particular emphasis include spawning of individuals in captivity as well as early larval development and identification. At this time, there are approximately 125 individual rockfish in the aquarium comprising eight Sebastes species. These include the kelp rockfish, brown rockfish, vermilion rockfish, black-and-yellow rockfish, gopher rockfish, copper rockfish, grass rockfish andtreefish. These fish have been collected over the course of the last two years from various locations within the southern California Bight, mostly from the nearshore areas of the Channel Islands
. Gravid females of brown, black-and-yellow, kelp and copper rockfish brought in from the field have yielded larvae in captivity. Copper and black-and-yellow rockfish larvae were maintained for 14 days and brown and kelp rockfish larvae were maintained for well over 60 days, providing new and exciting information about their early growth and development.
Efforts are now focused on inducing the rockfish broodstock to spawn naturally in the aquarium under a carefully controlled environment, including temperature and photoperiod manipulation, designed to trigger the rockfishes reproductive cycles. In this way, we hope to be able to provide larvae for further investigations on a fairly regular basis, in addition to the fishes' normal spawning season. Much remains to be learned about rockfish larval diet and environmental requirements. Such life-history information is of extreme importance in efforts to effectively manage these important fish stocks that are under ever-increasing human and environmental pressures.
Another research project, recently completed in the SWFSC aquarium, involved a graduate student's work examining the effects of extreme levels of temperature and low dissolved oxygen on the otoliths and growth of Tilapia, Oreochromis mossambicus, as part of a master's thesis with San Diego State University. The research is part of a larger research program investigating the fisheries ecology of the Salton Sea and is supported by a grant through the Salton Sea Authority and funded by the Environmental Protection Agency.
Also, in conjunction with the California Department of Fish & Game, work is being carried out involving the market squid, Loligo opalescens. Masses of squid egg cases have been collected locally by scuba divers and are being incubated in a specially designed holding tank. Upon hatching, squid larvae are regularly sampled and preserved to be used for age-validation and developmental analysis.