This article describes the growth, mortality, and selection patterns in early larval stage of Japanese seabass Lateolabrax japonicus in Ariake Bay, Kyushu, Japan. Japanese seabass larvae were collected from the spawning ground in December 2007, and juveniles
were collected from the nursery ground in March 2008. Otoliths were analyzed to produce daily records of size-at-age and growth
rate that were compared between larvae and juveniles to determine whether selective mortality occurred. A weight-specific
growth coefficient (G) and instantaneous mortality coefficient (M) were computed, and the recruitment potential was evaluated from the ratio of M:G. Selection for fast-growing and bigger larvae was evident during the 5–14 days after hatching (DAH). Selective mortality
acted to preferentially remove fish that were slow growing and/or relatively small members of the cohort at least during the
period examined. Trends in the growth rate differences between larvae and juveniles suggested that the selection process continued
beyond 14 DAH although the exact duration over which selective mortality occurred was unknown. Survivors of Japanese seabass
exhibited traits consistent with all aspects of the ‘growth–mortality’ hypothesis: faster growth, larger size-at-age, and
shorter larval stage duration (LSD), i.e., larvae with faster growth, bigger size-at-age and a shorter LSD selectively survived
the larval period. Larvae had higher M (0.323) than G (0.159), resulting in the M:G ratio of >1.0 (M:G = 2.031), suggesting that the larval cohort was rapidly losing biomass. Future studies should look to determine the duration
over which selective mortality occurs and the timing of transition between M and G (M = G) and accumulation of cohort biomass.
Keywords Selective mortality - Growth coefficient - Mortality coefficient - Recruitment potential - Japanese seabass -
Lateolabrax japonicus
- Ariake Bay
The online version of the original article can be found under doi:10.1007/s10452-009-9271-6. Introduction to the errors and the corrections made in this erratum: The authors apologizes that the original of the above mentioned article contains some serious errors that are corrected in
this erratum. Figure 3 in the original article shows that larval size is decreasing at 0−8 days but this is not realistic;
in normal circumstances, size should increase with age. Our investigations have confirmed that the size-at-age presented in
Figure 3 in the original article was incorrect and that the error was caused by the model used for back-calculation of size
from otolith radius (OR). When we plotted OR-at-age as proxy for size-at-age, we found that size was actually increasing consistently
with age (see the new Fig. 3 in this erratum) confirming that the back-calculated sizes were incorrect.
We used the ‘biological intercept’ method (BIM) for back-calculating size-at-age. The method gave incorrect size estimates,
possibly because of two reasons: (i) the method assumes a linear relationship between OR and fish size but the relationship
was allometric in our study; and (ii) values of the biological intercept (fish size and OR at first feeding) used in the model
were perhaps not applicable for larvae in this study. In addition, the BIM itself is often biased and produce erroneous size-at-age
estimates (see Takasuka et al. 2004 for discussion). In order to avoid possible biases and errors from back-calculation, many previous studies have used otolith
data only and not back-calculated data (e.g., Hare and Cowen 1995; Searcy and Sponaugle 2001; Shima and Findlay 2002) because otolith data are more direct than back-calculated data.
In order to correct the errors, we have omitted the back-calculation step and presented the otolith data in this erratum.
Since there was highly significant relationship between OR and fish size (standard length, L), we used otolith daily increment width (DIW) as a proxy for growth rate and OR-at-age as a proxy for size-at-age. The original
Fig. 3 has been completely replaced by a corrected version and corresponding changes have been made in the texts. Since DIW
data has been added to show growth history in the new Fig. 3, the original Fig. 4 is no more useful and has been deleted.
The reference Islam et al. (2009) has been updated.