Advisor(s)
Stephen Watts
Committee Member(s)
Cynthia Tant
James McClintock
Thane Wibbels
Victoria Gibbs
School
College of Arts and Sciences
Document Type
Dissertation
Department (new version)
Biology
Date of Award
9-11-2025
Abstract
This dissertation seeks to further knowledge of sea urchin husbandry in three major areas that have so far not been investigated substantially: optimal conditions for housing sea urchins in a lab-based recirculating aquaculture systems (RAS), impacts of repetitive spawning regimens on reproductive output, and co-culture utilizing juvenile oysters. All studies utilize a commercial recirculating aquaculture system that is relatively novel for culturing sea urchins. The first chapter investigated the influence of housing conditions on sea urchin growth outcomes. Under the conditions of this study, the size of the tank showed limited influence on growth; however, stocking density was found to inversely alter growth outcomes. Sea urchins held at higher stocking densities showed decreased feed intake, decreased dry matter production, decreased gonadosomatic index, and reduced survival. Additionally, while spine breakage was not found to be influenced by tank size, it did increase as stocking density increased, which was attributed to intraspecific interactions. Also seen in the higher stocking density treatment was a disparity in spine regeneration, with females having less spine regeneration compared to males. The second chapter tested the impacts of repetitive spawning on reproductive output in sea urchins held in culture. Spawning was induced by KCl injections on or around the new moon from April through December. Little difference in growth, gamete production, and welfare outcomes was seen between sea urchins spawned every month compared to those spawned every other month. All sea urchins showed a reduction in growth during the latter half of the experiment, which could be attributed to spawning fatigue or potassium toxicity. The disparity in spine regeneration was similar to that in the first chapter, with females having less regeneration compared to males. The final chapter investigated viability of housing sea urchins with juvenile oysters. Sea urchins of both ca. 7.5-mm and 34.5-mm diameters did not consume small oysters (8.5-mm and ca. 16-mm shell heights) when held sympatrically in culture tanks. Sea urchins did use live oysters in a covering response. In addition, sea urchins were found to substantially clean oyster shells of biofouling under all conditions.
ProQuest ID
Recommended Citation
Edwards, Raven Amber, "Standardizing Sea Urchin Husbandry: Tank Effects, Gamete Production, And Co-Culture" (2025). All ETDs from UAB. 7402.
https://digitalcommons.library.uab.edu/etd-collection/7402
