By Staff Reports
(Honolulu)– A research effort at the Oceanic Institute (OI) has created aquaculture techniques that may someday lead to production capability of one of the world’s most popular aquarium fish — a development that could both help the aquarium industry and protect Hawai‘i reefs where wild varieties of the brightly colored, arrow-shaped fish are harvested now.
OI research scientist and principal investigator Chatham K. Callan, Ph.D., says more than 300,000 yellow tang (Zebrasoma flavescens) are collected in the wild and exported from Hawai‘i annually, showing the strong demand for the fish. OI — a research and teaching affiliate of Hawai‘i Pacific University — is developing new breeding techniques that could make it possible to eventually breed yellow tang from eggs cultured in aquaculture settings.
The development is detailed in the new issue of Global Aquaculture Advocate, in an article by Callan and his colleagues in the OI Finfish Department, Melissa D. Rietfors, Michael Dean Kline and Eric W. Martinson, and Charles W. Laidley, Ph.D., of the Waikiki Aquarium, University of Hawai‘i at Manoa.
“This research is a significant first step toward a viable, cultured supply in the future,” Callan said of OI’s continuing work.
OI began focusing on research to culture yellow tang in 2001, with financial support from the Center for Tropical and Subtropical Aquaculture, NOAA Hawaii Sustainable Fisheries Development project and NOAA Marine Aquaculture Program. At beginning, there were little to no viable eggs, said Callan, but through the years, “we’ve improved radically, not only in total eggs but also quality of eggs.”
With significant progress in recent years, OI researchers can achieve a monthly yield of more than 1 million eggs, with a mean fertility rate of 84 percent and an egg viability rate of 51 percent, according to the new article. This can be attributed to better broodstock selection, developing an effective larval rearing system, and — most importantly — identifying suitable feed.
“Successful feeding so that they can live through the first few weeks was a bottleneck” for earlier researchers, Callan said. “We’ve developed rearing methods for both the larvae and their prey enabling them to eat and survive through this critical first-feeding stage, which up until now, has not been achieved.”
A recent study by the National Oceanic and Atmospheric Administration (NOAA) found that the reefs in Hawai‘i are worth about $34 billion annually for conservation, recreation and seafood. “Alternatives to harvesting wild fish for consumption and aquarium supply are urgently needed to help protect this invaluable resource,” according to Callan and his collaborators, in the article.
OI’s research addresses the need for better production methods, Callan said. “Aquaculture is already providing a significant portion of the world’s fish supply and is projected to comprise more than 60 percent of total production by 2020,” he said.
For more details on OI’s yellow tang feeding and rearing breakthroughs, read the article in Global Aquaculture Advocate online at http://www.gaalliance.org/mag/2013/Jan-Feb/index.html. Contact Callan at (808) 259-3149 or ccallan@oceanicinstitute.org.
Founded in 1960 as the Makapu‘u Oceanic Center by the Pacific Foundation for Marine Research, OI has grown and diversified over the years on a 56-acre site on the windward side of O‘ahu, adjacent to the Sea Life Park tourist attraction. It is home to researchers and technicians, as well as marine science faculty researchers and graduate students from HPU, who conduct scientific studies and collaborate with OI staff both on site and on ocean-based projects.
In addition to its aquaculture work, OI is focusing research on livestock feed as part of a pilot program to produce animal feedstock in Hawaii, addressing one of the most costly challenges for local livestock operations. It recently hosted a Hawaii Department of Agriculture workshop on the subject with HDOA Chairman Russell Kokobun that brought together industry representatives from around the state to brainstorm approaches to overcoming feedstock challenges.
Hawai‘i Pacific University is the state’s largest private university with more than 8,000 students from the United States and more than 80 foreign nations. HPU is accredited by the Western Association of Schools and Colleges, the Council on Social Work Education, the National League for Nursing Accrediting Commission, and the Commission on Collegiate Nursing Education.