On the Age and Growth of the Labroid Fish Halichoeres poecilopterus from the Seto Naikai, Japan

Abstract

The age and growth of the labroid fish Halichoeres poecilopterus from the Seto Naikai were estimated by examining the scales based on the specimens collected from the Seto Naikai from 1981 to 1984. With respect to the results of our study, one annulus of each scale is formed once a year in the hibernating period from January to April. This species spawns in early summer from late June to July, based on the temporal fluctuation in gonad index of the female. At the age of 1, 2, 3, 4 and 5 years old, the fishes are 61, 86, 106, 124 and 140mm in standard length, respectively, as estimated by the marginal growth indices. The general growth of the fish is presented by the following formula described by B_ERTALANFFY:
L_t(mm)=234.8{1-e^{-0.151(t-0.986)}}.
The length(mm)-weight (g) relationship of this species is given by the formula, W=4.886×10^-6L^3.280. Consequently the asymptotic weight is estimated as 291.6g.
The mean standard length of the immature yearlings collected in December, 1983 and 1984, were 42.4 and 42.3mm, respectively. The back-calculated standard lengths of yearling fishes in early summer are expected to be 44.7mm in December. The back-calculated standard lengths of the yearling are almost equal to their actual standard length.