Experimental rearing of juvenile New Zealand turbot Colistium nudipinnis (Waite 1910): a potential new aquaculture species
Aquaculture
Research, 32(9): 727-737
Abstract:
Investigations into factors affecting the growth of
the first hatchery-produced juvenile New Zealand turbot Colistium
nudipinnis (Waite 1910) showed that this endemic flatfish can be reared
in raceways and tanks. After initial high mortality (> 60%) in the
post-weaning period (to 120 days post-hatch), the juveniles showed high
survival over the grow-out period. Growth of the juveniles was better at
lower (16–18 °C) than at higher (> 20 °C) water
temperatures, and better in a deep tank than in shallow raceways. Under the
experimental rearing conditions, growth (to mean weight of 0.2 kg in 20 months)
was relatively slow and food conversion (FCRs > 1.4) relatively
high, both factors being related to the feeding behaviour of this species. C.
nudipinnis feeds directly from the bottom, and this behavioural
characteristic influences aspects of fish farming practice, such as stocking
density and feeding strategy, that are critical to its economic viability.
There is potential to improve the growth by optimizing the rearing
conditions, so that it may not be unrealistic to achieve the maximum growth
reached in these trials commercially and produce marketable farmed turbot,
of over 400 g weight, within 2 years.
(National Institute for Water and Atmosphere, PO Box
14-901, Kilbirnie, Wellington, New Zealand)