Sustainable Aquaculture of the Green Urchin
Within the past decade, commercial harvesting of the green sea urchin, Strongylocentrotus droebachiensis, in Maine and New Hampshire expanded rapidly and became the second largest fishery in the state of Maine, behind lobsters (Harris et. al., 1996). Since then the fishery has been declining due to overfishing. This has led to a great interest in developing a plan for a more sustainable fishery and, thus, a growing interest in the aquaculture of sea urchins.
This experiment was designed to investigate ways of planning a system for the culturing of urchins from larvae through the metamorphosis stage to produce seed stock for outplanting. Three species of algae were cultured to be used as the variable treatments: Nanochloropsis, Isochrysis galbana and Dunaliella. Measurements of the arm spicules in the three different treatments were made weekly and no significant differences were found between treatments.
Results indicate that Nanochloropsis may be the most suitable algae for urchin aquaculture. Such a diet led to a greater amount of settlement than that of an Isochrysis diet. However, the test sizes of urchins fed Nanochloropsis were found to be significantly smaller than those of urchins fed an Isochrysis diet. It may then be suggested that a larger ration of Nanochloropsis would be the most sustainable diet.
Available from the National Sea Grant Library (use NHU number to search) or NH Sea Grant
- S.A.G.U.: sustainable aquaculture of the green urchin (1997). Nathan Lake, Angeliki Karapanos and Jennifer Johnson. Advisor: Larry Harris.