Culturing Native Species of Macroalgae in Hawai`i and the U.S. Affiliated Pacific Islands
|University of Hawaii at Hilo
|Maria Haws, Ph.D.
- Asparagopsis taxiformis (limu kohu) was chosen as a model species due to its high value, high demand, and intense level of interest by aquaculturists. Experiments will be conducted to determine the environmental and culture factors required to promote optimal growth and survival of both life stages of A. taxiformis. Culture trials will be conducted testing factors such as stocking density, light, photoperiod, temperature, salinity, tank volume, water movement, flow/water exchange rates, and nutrient regimes to determine effects on growth and survival rate. Work will begin with small cultures, and will be scaled up until commercial quantities are reached.
- Test tumble culture of Codium edule. Although C. reediae is currently cultured in Hawai`i, C. edule is considered to have superior flavor, but has not been commercially cultured. Tumble culture is the preferred culture method as it eliminates the need for substrates, lends itself to more rapid growth, and reduces post-harvest cleaning time since there are no particles adhering to holdfasts.
- Once environmental and culture requirements of the two algal species have been precisely characterized, a culture system(s) will be designed and tested that is appropriate for each species.
- Outreach will be conducted through publishing findings in a manual for use by local aquaculture stakeholders, as well as in scientific publications. An Aquatips article will be contributed. Interested stakeholders will also be invited to visit and observe the trials at the PACRC during a workshop to be held there. Further outreach will occur through establishing similar demonstration units at MERIP (Pohnpei) and UOG (Guam) to enable these institutions to conduct similar trials with native species of macroalgae (Asparagopsis taxiformis, Codium sp., Halymenia sp. and Caulerpa sp.), and to provide training opportunities for industry, educators and students. No transfer of non-native species will take place. The graduate student involved in this work will draft and submit a thesis on the topic.