The effects of tank system, water velocity and water movement on survival, somatic and gonad growth of juvenile and adult green sea urchin, Strongylocentrotus droebachiensis

• Published in: Aquaculture research Vol. 46; no. 6; pp. 1501 - 1509
• Main Authors: James, Philip, Siikavuopio, Sten Ivar
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.06.2015; Hindawi Limited
• Subjects: 'laminar' and 'tipper' systems; somatic and gonad growth; Strongylocentrotus droebachiensis; tipping frequency; water velocity
• ISSN: 1355-557X; 1365-2109
• DOI: 10.1111/are.12303

The effects of water velocity and tipping frequency (water movement) on survival, somatic and gonad growth of juvenile and adult green sea urchin, Strongylocentrotus droebachiensis were investigated. Juvenile and adult urchins were held in ‘laminar’ or ‘tipper’ tanks. Both were supplied with three inlet water flows (1.5, 3.0 and 7.5 L min−1) which converted to water velocities of 0.28, 0.57 and 1.43 cm s−1 in the ‘laminar’ tanks and tipping frequencies of 30, 10 and 5 s in the ‘tipper’ tanks. Juvenile sea urchins had significantly lower mortality and greater somatic growth when held in ‘laminar’ flow tanks compared with ‘tipper’ tanks. The varying water velocities tested in the ‘laminar’ flow treatment had no effect on the growth of juvenile sea urchins. The juvenile sea urchins in the ‘tipping’ treatment held at high tipping frequency had significantly slower growth than those in the medium and low tipping frequency treatments. There were no differences in mortality or gonad growth in the adult sea urchins regardless of treatment. The ‘laminar’ flow tanks retained significantly more organic material compared with the ‘tipper’ tanks. The authors discuss the effects of water velocity and tipping frequencies in system design for aquaculture of sea urchins.