The first-feeding response of larval southern bluefin tuna, Thunnus maccoyii (Castelnau, 1872), and yellowtail kingfish, Seriola lalandi (Valenciennes, 1833), to prey density, prey size and larval density
Hilder, PI and Cobcroft, JM and Battaglene, SC, The first-feeding response of larval southern bluefin tuna, Thunnus maccoyii (Castelnau, 1872), and yellowtail kingfish, Seriola lalandi (Valenciennes, 1833), to prey density, prey size and larval density, Aquaculture Research, 46, (11) pp. 2736-2751. ISSN 1355-557X (2015) [Refereed Article]
We investigated the first-feeding success of two
species: southern bluefin tuna (Thunnus maccoyii)
and yellowtail kingfish (Seriola lalandi) to determine
if similar culture parameters can be used for
both, especially when S. lalandi are held in the
same tanks as prey for T. maccoyii. The feeding
performance (proportion and intensity) was examined
in three short-duration (4 h) experiments:
prey density, prey size and larval density. Increasing
prey density from 0.5 to 25 rotifers mL
increased the proportion of T. maccoyii and S.
lalandi larvae feeding. Prey size alone did not affect
feeding in either species. Seriola lalandi had a
decreased proportion of larvae feeding when larval
density reached 50 larvae L
-1 concurrent with a
gradual increase in feeding intensity between 2
and 50 larvae L
-1. In T. maccoyii, there was no
pattern to the effect of larval density on the proportion
of larvae feeding. The overall feeding performance
of larvae was higher in T. maccoyii than
S. lalandi. Increased prey density improved the
first-feeding ability of T. maccoyii and S. lalandi larvae.
The effect of larval density on S. lalandi feeding
requires further investigation, to ensure that
they remain feeding when provided as prey in T.
maccoyii culture. The identification of factors in
this study, which increase first-feeding success, will
improve the culture of both species.