The effect of temperature on first feeding, growth and survival of larval witch flounder, Glyptocephalus cynoglossus
Witch flounder Glyptocephalus cynoglossus has recently been identified as a candidate species for aquaculture in the northeastern United States and the Canadian Atlantic Provinces. This study investigated the optimal temperatures for witch flounder larval first feeding and for long term larval culture from hatching through metamorphosis. Maximum first feeding occurred between 15.0 and 16.2 C. Larvae did not survive beyond first feeding when reared at mean temperatures of 5.1, 10.4, or 19.5 C and were unable to initiate feeding at mean rearing temperatures below 6.0 C. At a rearing temperature of 15.0 C in 16‐L tanks, mean larval survival to 60 days post hatch (dph) was 14.1%. Mean overall length‐specific growth rate for larvae reared to 60 dph at 15.0 C was 3.5%/d and mean absolute growth was 0.62 mm/d. Subsequent larval growth at 15.6 C began to taper off towards 70 dph at the onset of weaning which overlapped with larval metamorphosis. Growth plateaued at 85 dph, followed by a rebound between 90 and 95 dph. Survival was 100% when weaning onto a dry, pelleted diet was initiated at 70 dph with a 10‐d live diet co‐feeding period. These results are favorable and encourage the further pursuit of commercial witch flounder culture.
Journal of the World Aquaculture Society
Digital Object Identifier (DOI)
Bidwell, D.A. and W.H. Howell. 2001. The effect of temperature on first feeding, growth and survival of larval witch flounder, Glyptocephalus cynoglossus. J. World Aquaculture Society 32:373-384.