World Aquaculture Singapore 2022

November 29 - December 2, 2022

Singapore

IMPROVED SEEDSTOCK PRODUCTION OF QUAHOG Mercenaria mercenaria AND AMERICAN OYSTER Crassostrea virginica FOR REMOTE SETTING

 Jesse Ronquillo* and Audrie-Jo McConkey

 

 Faculty of Trades and Technical Programs

 North Island College

 1565 South Dogwood Street

 Campbell River, BC, Canada  V9W8C1

 Jesse.Ronquillo@nic.bc.ca

 



Quahog or hard clam (Mercenaria mercenaria) and American oyster (Crassostrea virginica) are important bivalve mollusks in North America. The demand for these species is strong but the traditional sources of supply are low and some culture sites have suffered catastrophes. In partnership with Gulf Aquaculture Association (GAA) based in Northumberland Strait, Nova Scotia, Canada, we devised less costly and innovative procedures in the spawning and larval rearing of quahog and American oyster to produce the needed seedstock. Selected species of microalgae rich in highly unsaturated fatty acids (HUFA) were mass-produced continuously in an inventive way to provide abundant and diversified source of live feeds to larvae until they reach pediveliger or eyed-larvae that were used by shellfish growers in Northumberland Strait for remote setting.  About 100 million of quahog seedstock and more than 500 million pediveligers or eyed-larvae were produced for remote setting and grow-out operations of shellfish growers in Northumberland Strait. The preliminary research outcomes include: (1) Design and construction of a prototype closed-culture system for controlled quahog and oyster spawning; (2) Successful induction of broodstock spawning based on environmental manipulation among desiccation, temperature shifts, UV-filtered water stimulation, microalgal addition, and various combinations of the above; and (3) Successful development of inexpensive system for efficient and continuous culture of microalgae for feeding the clam and oyster seedstock.