Date of Award

Spring 2019

Degree Type

Masters Thesis

Degree Name

Master of Science (MS)


Ocean Science and Engineering

Committee Chair

Eric Saillant

Committee Chair School

Ocean Science and Engineering

Committee Member 2

Reginald Blaylock

Committee Member 2 School

Ocean Science and Engineering

Committee Member 3

Jeffrey Lotz

Committee Member 3 School

Ocean Science and Engineering


The spotted seatrout (Cynoscion nebulosus) is a euryhaline finfish candidate for marine aquaculture in the northern Gulf of Mexico. Aquaculture of this species currently uses salinities of 25 psu or greater making production challenging in areas where high salinity water is not available. This study aimed to document the effects of salinity on zootechnical performance of spotted seatrout embryos, early larvae, and juveniles in recirculating aquaculture systems to assist with the development of protocols for low salinity culture.

Embryos obtained from a volitional spawn at 29 psu were incubated at three salinities (12.5, 18.75, or 25 psu) until unfed larvae expired. The neutral buoyancy salinity of embryos was 25 psu in all groups. Hatch rate was reduced in the 12.5 psu group where embryos tended to fall out of suspension, but larval survival post-hatch did not differ between treatments. Vitelline reserves were utilized more slowly in the lower salinity treatment groups than in the high salinity treatment.

Juveniles from two age groups (42 and 210 days old) were cultured in parallel for 267 days at four salinities (10, 15, 20, 25 psu). The 15 psu group was lost due to a parasitic infection early in the experiment. Survival in the other groups was low (average ~12%) but did not differ between treatments. Total length was highest in the 10 psu group. These results suggest that embryos and newly hatched larvae tolerate low salinity culture after hatch, and that grow out of juveniles at low salinity would be beneficial.