The effect of salinity on
growth and survival of juvenile black bream (Acanthopagrus butcheri)
G.J. Partridge, G.I. Jenkins-2002
Aquaculture, 210(1-4): 219-230
Abstract:
Growth and survival of juvenile black bream (Acanthopagrus
butcheri) were determined at salinities from 0 to 60 ppt (in 12-ppt
increments) and from 0 to 12 ppt (in 4-ppt increments) in two separate
trials of 6 and 4 months duration, respectively. Juvenile black bream were
able to survive and grow at salinities ranging from freshwater (0 ppt) to 48
ppt. Osmotic stress was evident at 60 ppt, however, survival was not
significantly affected. Fish reared at 24 ppt in trial 1 had a specific
growth rate of 2.34±0.03%/day, a rate significantly higher only to those
fish reared at 60 ppt (2.16±0.04%/day). Growth was greater at 24 ppt in
association with the highest food intake and most efficient FCR. Although
both food intake and FCR were not significantly higher than those obtained
with fish reared at 12, 36 and 48 ppt, the combination of the two factors
being optimised at 24 ppt lead to the greatest growth. Analysis of data from
the second trial found no significant difference in the growth rate of black
bream reared at salinities ranging from freshwater to 12 ppt, with SGR
ranging from 1.92±0.05%/day to 2.05±0.02%/day. Variable results in
freshwater between the two trials suggested that total hardness of
freshwater may influence survival and/or an ontogenetic change in salinity
tolerance may occur.
(Aquaculture Development Unit, WA Maritime Training
Centre, 1 Fleet St., Fremantle, Western Australia 6160, Australia, Tel.:
+61-8-9239-8032; fax: +61-8-9239-8081, e-mail: partrg@fleetst.training.wa.gov.au)